The Moveable Garden

Creating Instant Garden Pizzazz is Easy!

Gardening in containers isn’t just about putting plants where they wouldn’t normally grow, being able to move tender plants inside during the winter, or growing plants that would struggle in your indigenous garden soil. The joy of growing in containers is this and more – having the freedom to move a plant at whim or the enjoyment of having plants at nose or eye level.

Versatile, eco-friendly, and creativity inspiring, container gardening is adaptable to any type or size of garden. It is simply growing plants in a receptacle that is not fully open to the garden soil. And containers can be much more interesting than an ordinary clay pot. Consider growing plants in a holey boot, rusted wash basin, enamel tub, stone sink, or leaky livestock watering trough – the possibilities are only limited by your imagination.

An overflowing container full of diverse textures and colors at the Dallas Arboretum

An overflowing container full of diverse textures and colors at the Dallas Arboretum

Today, half of all plants bought in garden centers and nurseries end up planted in containers. The attraction? It makes us feel good to have some of our favorite plants close by where we can view them frequently and care for them easily. This means plants near the front and back doors, hanging from window sills and sitting on the patio.

Using containers in the garden is a great way to add diversity and flexibility. Containers are my solution to coping with an inhospitable, gravelly, lean soil and unforgiving, intense sunlight. With containers, I can grow the plants that I like and I grow them where they thrive best – instead of being restricted to growing only the plants that will survive in full sun on droughty soils. In my case, thanks to numerous containers, I garden under a large oak tree, on the patio, and under the front porch overhang. I can now grow fresh herbs: basil, mint, coriander, and dill; showy flowering plants like the pretty mini petunias called Calibrachoa; try a new dwarf butterfly bush shrub, and have success growing Iresine ‘Blazin’ Lime’ with its tender but pretty foliage colors, all that I would not have been able to grow in garden beds.

Having fun with plants and containers can lead to some really creative pairings

Having fun with unusual plants and containers can lead to some really creative pairings.

Containers make gardening happen … anywhere. For people that like to rearrange the furniture, containers make quick work of filling in a blank spot, adding pizzazz to a dull area, hiding an unsightly object or just creating a new spur of the moment accent.

The uses for container plants are quite varied; to move tender plants outside for the summer, to grow specialty plants that require a different soil mixture, to restrict plant growth through bonsai or penjing, to control invasive plants such as the notorious mints, to create small-scale water gardens, and they really are the best way to display weeping or trailing plants. Container gardens are also an economical way for a new homeowner or beginning gardener to get started, they require no digging and little weeding, and are easy to change the soil or plants from year to year. Best of all, if you become really attached to your plants and have to relocate, like I have done – your container garden can move with you.

It’s not all easy gardening though – containers do take a bit of planning so compatible plants are selected. Not all plants are suitable and many full-sized vegetables are better grown in the ground. Containers limit the ultimate size of plants too. So if you are planning to grow the world’s tallest tomato plant, don’t settle for anything much smaller than the world’s largest container either. Container gardening takes more of a commitment than in-ground growing, often requiring rigorous watering, fertilizing and pruning routines. Miss one watering during a critical hot, dry day and the result could be stressed out plants. Hot, summer winds also cause plants to dry out faster in containers and mature plants have a tendency to blow over when the soil dries out. There’s also the possibility of salts building up in the soil and the need for leaching to flush this out. And lastly, it’s easy to overwater plants if drainage holes get plugged.

Easy Designing Tips

First think about your garden style. Try to match your container to the style of your garden. Is it formal, informal or cottage style, new American garden style with masses of native plants and ornamental grasses, or is it a garden of reclaimed objects with a tractor tire planters and bottle trees? After matching the style, consider the number of different materials (stone, brick, wood, metal, glass, plastic) that are being used in the hard landscape and try not to exceed more than three or four types including the containers.

Often containers are just as important to the overall visual display as the plants they hold.

Often containers are just as important to the overall visual display as the plants they hold.

Containers provide structure for living plants and should be included as part of the hard landscape plan. Don’t have so many “hard” features that they detract from the plants and steal away the impact. A garden is for plants, right?

Consider the balance or scale of the container to the plants. Avoid a top heavy or bottom heavy design. Use trailing or upright plants to get the right scale. The size (weight or mass) of the container should be equal or ½ of the collective volume of the plants. Generally, balance is achieved by following a 1:1 or 1:2 pot to plant height ratio rule.

Relate the size of the container to the number of plants that will comfortably grow to fill the space. Think two months down the road and give them enough room to grow. Yes, the container will look a bit sparse at the start but the plants will be healthier this way. I haven’t seen any ready-made containers at the nursery that weren’t planted too full and wouldn’t need serious “editing” two weeks later. Don’t fall into this trap too.

Which plants?

Choosing suitable plants can’t be stressed enough. Conditions are tough for plants growing in a container so don’t pick wimpy plants that need tons of pampering (i.e.: watering twice a day during the summer) to survive. Also make every plant count in the container. Since space is limited every plant must contribute, be it for texture, contrast, foliage color, flower power, scent or seed pods. The smaller the space the more critical good planning about plant selection is!

What colors are preferred? Do you like restful and harmonious (blue, purple, pink) or hot and bold (orange & red) colors? Also consider the dramatic effect of contrasting leaf textures, shapes and sizes.

Consider how your community of plants will react to each other. Are all plants compatible? Are they all shade loving, like moist soil, or acidic soils? The more they tolerate similar conditions, the happier they will all be in the container.

Terra Cotta is a Popular Container Material

Terra cotta is a traditional container material that might be hard to use in the garden but with the right complementary plant foliage colors, a dramatic display is possible for the patio.

Next think about the maintenance requirements of your containers. Are you willing to water 3x a day, which may be required if growing a large, thirst plant in a small pot? This is important! Plants in containers require more attention than plants growing in the ground. Here are several good tips to consider if you aren’t willing to commit to watering containers at least once a day during the hottest part of the summer. Use extra large containers, add water-holding polymers to the soil, use mulches, add more compost to the soil, install drip irrigation, garden in the shade or semi-shade, and using glazed containers will help conserve water so that containers won’t need such frequent watering.

About Selecting Containers….

Consider the size. Can it be moved? Larger containers hold moisture longer, but they do get heavy. Two recently watered, large containers ended up being too heavy for me to move into the garage ahead of plummeting temperatures last fall and I had to take my chances that the plants would survive snug against the house (luckily they did). Larger containers have more room for root growth which means healthier plants. Don’t skimp on container size, even shallow-rooted vegetables like lettuce, radishes, beans, and peas should have at least 6” of soil and will often grow much better in deeper soil.

Consider container stability. Does it have a narrower base and will be blown over in the wind? Watch out for tall, top-heavy plants that will make the container even more unstable.

Is drainage needed? For all plants except water gardens, drainage holes are critical. Plan to have at least one hole (>0.5 inch) for every 6 inch base. It is recommended that a 30 gallon container have at least eight drainage holes (of 1 inch diameter).

Pot feet or bricks are used to raise containers above the ground and help significantly with soil water drainage. They also decrease the chances of soil pests entering the container and the risk of rot with wood containers or decks.

In hot environments, the color of the container should be considered. Is it light colored and will reflect, or dark and absorb heat?

Recycled Containers

Scour flea markets, garage sales and antique stores. There’s no reason for boring planters. How much fun would it be to create a garden in a rusted out wash tub? Terra cotta stove tiles are also a great container material, or a beat up mailbox, leather boot or wooden shoe, leaky aquarium (now technically a terrarium), rusted out watering can, weathered straw garden hat … well the possibilities are almost endless.

Soil for Containers

The Choices are Almost Endless

Look around and you may find tropical plants like this asparagus fern that are perfect for your next moveable garden. Many other tropical plants, flowering annuals or perennials and even compact vegetables work well in containers. Add some dramatic impact to your next garden plans.

When I plant a container, I have yet to find a packaged soil that I don’t feel I have to modify. Either they are too peat mossy and need some compost or they are too heavy and need sand or vermiculite to lighten them up. So I end up mixing up my own recipe. My advice, mix your own too! For organic growing, unless you know and trust your supplier, you are better off making your container mix with your own soil. Here’s a basic recipe: finished, sieved compost (4 parts), coarse sand (1 part), vermiculite, perlite or turface (1 part) and a recommended amount (from the label) of slow-release, granular organic fertilizer. This recipe can be adjusted with additional of peat moss or shredded coir, ground limestone, superphosphate, kelp, etc. depending on soil tests and the type of plants being grown.

Container Material Choices


  • holds moisture
  • some look cheap
  • some realistically look like stone
  • light weight and might blow over
  • might break down over time from UV rays.
  • inexpensive
  • versatile and available in many sizes and colors

Terra cotta

  • traditional container material
  • sometimes a design challenge because of its color
  • with age will develop mossy look
  • might disintegrate if exposed to freezing and thawing (particularly thin, lightweight types)


  • prone to rot
  • needs repeat painting
  • easy to use for larger scales and unique sizes or shapes
  • longer lasting teak/cedar expensive
  • wood preservative toxic concern


  • for lime loving plants only (or needs leaching)
  • color additive expands opportunities
  • strong & can be overwintered
  • can make it age faster with moss and yogurt


  • copper will oxidize to a patina color
  • rusts

Edible Plant Suggestions for Containers

Herbs: mint, basil, chives, thyme, oregano, marjoram, dill, cilantro, lavender, rosemary, horseradish, sage, parsley

Vegetables: lettuce, some tomatoes, peppers, eggplants, chard, pak choi, potatoes, cauliflower, broccoli, carrots, garlic, cucumber, onions, cabbage, beets, kohlrabi, green beans, spinach, turnips, some squash. Check out the new mini vegetable cultivars for containers.

Fruits: strawberries, grapes, blackberries, gooseberries, olives, figs, raspberries

Don’t overlook mixing vegetables and flowers together and the benefits of companion planting.

Bird-Friendly Winter Gardens

Gardening for the Birds

Nothing helps relieve that “cabin fever” feeling during a long winter better than gazing out the window and watching birds play tag at the feeder or feeding on savory seeds plucked straight from your shrubs. Making your property more bird-friendly can attract and keep birds longer and create a pleasing landscape for you to enjoy too. For birds to make their winter residence in your garden, they need to have the basics: food, shelter and water. Shelter is easily managed with a few evergreen or conifers to provide protection from winter winds, ice and snow. Providing food and water is decidedly more challenging for birds when temperatures drop below freezing and the snow starts to pile up. Designing a garden to be bird-friendly during the winter months is no more difficult than designing an attractive year-round garden that contains persistent berries and seeds.

A bird-friendly garden (at any time of the year) can be accentuated by using a diverse group of native plants, designed so there are many layers of dense plants to attract a wide spectrum of ground dwelling to treetop birds. The ideal backyard bird habitat also has limited open areas where birds are exposed to predators and contains feeding stations, birdhouses and watering holes. A tidy garden where every inch is trimmed, blown, raked or swept leaves little of interest for birds. For birds, messy is better – so leave some dead branches upon which to perch, seedheads for food, and leafy debris to entice insect food.

Blue Jay in Algonquin Provincial Park, Ontario Canada

Blue Jay in Algonquin Provincial Park, Ontario Canada

Get to know the birds that stay around during the winter and their food preferences. This will allow you to select the best mix of plants for your landscape and maximize the food potential that your plants give. Observe which birds like to frequent the ground level, which ones prefer thorny shrubs or conifers and who likes to perch up high? Designing your garden with the favorite foods of your winter season birds will pay off with a steady stream of avian friends. For ground-level birds like mourning doves, juncos, sparrows and towhees consider planting perennials with overwintering seedheads, ornamental grasses and low shrubs like chokeberry or gray dogwood. For birds that like to be at shrub-level such as cardinals, finches and jays plant larger shrubs or small trees like bayberry, winterberry, sumac or vernal witch-hazel. To attract treetop birds such as the titmice, goldfinches or chickadees plant hackberry, hawthorn or conifers (also for tree trunk frequenting birds like woodpeckers, nuthatches or wrens).

Overall, though, design a garden that suits you. Don’t select all wild, natural shrub forms if a formal garden is what you want. There are still lots of formal-looking plants that are bird friendly if a formal garden style is what you want.

Female Northern Cardinal in the garden. Photo by GeoffClark

Female Northern Cardinal in the garden. Photo by GeoffClark

Don’t worry that you can’t include a favorite food plant for every bird that might visit your garden. The National Bird-Feeding Society reports that there are over 100 species of birds that visit bird feeders throughout the United States. You can’t attract a huge variation of birds from owls to hummingbirds to orioles to bluebirds to a small property. It’s not possible to get all the plants (food sources) and environments perfect for such a diverse group of birds. Narrow your garden design plan down to target the birds that are common visitors to your area and the ones that you like best.

In addition, don’t forget that using organic growing methods and non-toxic cleaning products and building materials outdoors will benefit your avian visitors.

Tips For a Bird-friendly Winter Garden

  1. Create several vertical layers of plants to attract a diverse range of birds.

Groundcover layer: mosses, partridgeberry

Perennial layer: thistle, golden rod, columbine, ornamental grasses


Appropriate for the perennial layer is the attractive Columbine plant which produces seeds that attract birds in the garden.


Shrub layer: dogwoods, nannyberry, spicebush, witchhazel, viburnums, sumac, cotoneaster, pyracantha, mountain ash, junipers, flowering dogwood, weigela, bayberry, roses, quince, winterberry

Staghorn sumac seedhead photographed in Hamilton, Ontario Canada

Staghorn sumac seedhead photographed in Hamilton, Ontario Canada

Vines: grapes, Virginia creeper (if it isn’t invasive in your area)

Tree canopy: crabapples, pine, spruce, fir, maples, elms, oaks

  1. Select a variety of plants that will provide food during the fall and winter months.

For the fall migration season, many southbound birds such as the thrushes, vireos, warblers and tanagers need fatty fruits to build up reserves for the long flight ahead. Good fruiting shrubs include dogwood, spicebush and mapleleaf viburnum.

For the overwintering birds, such as the finches, sparrows and waxwings, persistent fruits are needed when food supplies become scarce because of snow cover. Shrubs such as winterberry, snowberry, sumacs, viburnums and highbush cranberry will hold their fruit into the winter for birds.

For early spring, northward migrating birds such as bluebirds, robins and thrashers need persistent food (or uncovered food when the snow and ice melt) such as conifer seeds, bayberry, hawthorns, crabapples and sumac fruit.

  1. Plant clumps or groups of the same species so that good pollination takes place. This is especially important for dioecious plants such as hollies, bittersweet vines, fringe tree, spicebush, and mulberries with separate male and female plants. For larger dioecious trees such as mulberry, willow, and ash planting more than one may not be an option, so determine (if you can) that your plant is female and will produce fruit and not a male that will only produce pollen.
  2. Include some conifers or evergreens to provide shelter for birds to roost and safely ride out winter storms.
  3. Avoid using invasive non-native plants that crowd out native plants and reduce landscape diversity. These include avoiding using Norway maple, Chinese privet, European buckthorn, Oriental bittersweet, white mulberry and purple loosestrife.
  4. Plant spiny plants (such as evergreen holly or thorny barberry) under feeding stations to deter predator animals. Also consider putting squirrel baffles on bird feeders to keep squirrels and cats away.
  5. Include a year-round source of water for birds to drink and bath in. During below freezing weather use a heater to keep ice from forming on top of the water. Place the water 10 feet away from dense shrubs that could hide predators, close to an electrical outlet and hose, and in view of your windows. If heating the water is not an option, don’t worry, birds can get their daily allotment of water from their food and snow, but this requires a lot of energy for them.
  6. Put out bird feeders to supplement natural food. Keep feed replenished in the feeder so that wild birds become accustomed to finding food there. Set up feeders (more than one will be needed to provide the different mixes of feed needed to attract several bird groups) in late fall and maintain them through early spring until natural food sources are plentiful again.
Red-headed woodpecker at the bird feeder

Red-headed woodpecker at the bird feeder

About Commercial Birdseed Mixtures …

There is a considerable difference between commercial seed brands – both in what they contain and the birds they attract. The season that you are feeding should also determine what food is provided since bird needs change with their activities. Watch for commercial brands that have been bulked out with fillers like beans, cracked corn, wheat, milo, red millet, dried rice, lentils and halved peas. Only some larger birds can eat these dry ingredients. Oats in the birdseed mixture are also a nuisance to clean up below the feeder. The better ingredients to have in birdseed mixtures are sunflower seeds, and corn or peanut granules which all have a high fat content.

Mix Your Own Winter Bird Feed

Instead of purchasing commercial pre-mixed birdseed which may have a lot of filler, you can custom mix your own. The Cornell Laboratory of Ornithology suggests the following make-it-yourself recipe:

25 lbs black oil sunflower seed

10 lbs white proso millet

10 lbs cracked corn

Mix in a clean garbage can with a broom handle. Cover tightly to keep out water and rodents.

In addition, the Cornell Laboratory of Ornithology suggests that birds will relish leftover squash, pumpkin or melon seeds even more than black oil sunflower seeds. Just spread the harvested seeds out on trays to air dry. Once dry, they are ready to put out for the birds. Smaller birds will have trouble eating the bigger seeds and so the seeds can be run through a food processor first to make them easier to eat. The Cornell Lab also suggests that “Birds such as robins, thrushes, bluebirds, and waxwings don’t usually show up at feeders because seeds are not a major component of their diet. But you can still tempt them to dinner with an offering of fruit. Soften dried raisins and currents by soaking them in water, then offer them at your feeding station. Mockingbirds, catbirds, tanagers, and orioles will also find sliced fresh fruit attractive. You can offer fruit on a platform feeder or simply on a plate on the ground.” For more in winter bird feeding, including a handy chart given the preferred and readily eaten commercial seeds that the common winter birds eat, visit

Seed eaters (siskins, sparrows, grosbeaks, redpolls and crossbills) will also eat suet but prefer unsalted sunflower seeds, black oil sunflower seeds, sunflower hearts or chips, thistle/niger (Nyjer) seeds, raw crushed peanuts, millet and wild grains.

Insect feeders (chickadees, nuthatches and woodpeckers) should have animal fats, peanut butter (mixed with melted animal fat and cornmeal or rolled oats to cut down on the stickiness) or suet. Don’t use a mesh bag to hang your suet (birds can get trapped in the mesh).

Fruit-eating birds (pine grosbeaks and bohemian waxwings) rarely visit feeders but when the snow covers their natural food source (highbush viburnum, blueberries or dogwood berries) they will resort to a feeder if grapes, apples, banana slices or softened raisins are present.

And lastly, don’t forget to give birds some grit. In the winter when snow cover is prevalent, birds still need to eat grit to grind their food. So frequently put out some crushed eggshells, course sand, or commercial grit.

What is Niger/Nyjer?

The shiny, black oilseeds that finches adore was originally called niger for more than 40 years (named for the area that the African yellow daisy (Guizotia abyssinica) plant that produces the seed originally grew). The name was changed to Nyjer (and trademarked) in 1998 by the Wild Bird Feeding Industry to help clarify the pronunciation. Purple finches, goldfinches, song sparrows, pine siskins, buntings, redpolls, juncos and mourning doves readily eat Nyjer, a seed that is high in calories and oil content.

The prolific flower is commercially grown in Africa, India, Myanmar and Nepal. It is heat treated upon arrival in the U.S.A. to prevent selfseeding and weed seed germination (this APHIS requirement was put into place in 1985 after a shipment was found to be contaminated with dodder, a Federally designated noxious weed).

Nyjer is around 35% fat, 18% protein, 18% fiber and 12% moisture and since it has such a high oil content it can go rancid quickly. If it has an off smell or birds don’t flock to it, it may have gone bad. Sunflower and safflower seeds and other nuts can also turn rancid if stored too long or in a hot location.

Nyjer feeders have very small holes to prevent the seed from running out and limit birds to just one seed per visit. The holes are often placed below the perch for upside-down feeding (an acrobatic feat that is easy for goldfinches and pine siskins). Mesh or socks are also popular inexpensive feeders. The thick mess made by the hulls under a Nyjer feeder can often choke out grass and perennials.

After 20 years of research, Glenn Page has developed two EarlyBird varieties of Guizotia abyssinica that have short maturation requirements and are now commercial crops that are being grown in Minnesota and other North American locations. These niger seeds are frequently sold live and are not required to be heat treated to kill weed seeds like the imported types.


The Cornell Lab of Ornithology, 159 Sapsucker Woods Rd, Ithaca, NY 14850, phone: 800-843-2473, website:

Wild Bird Feeding Industry, P.O. Box 502, West End, NC 27376, phone: 888-839-1237, website

Break Out of Your Hardiness Zone

The Launch of a New Garden Hardiness Zone Map

Are more gardeners developing a fixation for hardiness zones and comparing notes across the back garden fence?  The recent launch of an updated plant hardiness zone map probably is causing more people to ponder the fine print on the plant label looking for the height, spread and hardiness zone details. Why the fixation with hardiness zones? Plant hardiness zones are valuable pieces of information that can save gardeners from lots of grief.

Not infallible, hardiness zones are far from 100% accurate though. There are restrictions in the types of data that are being used to create hardiness zones and most often these are just average minimum temperature weather records. It should be noted that plant hardiness involves so many more factors. Whether a plant survives the winter may be because it is growing in a microclimate right in your garden.

Microclimates play a big role in modifying the weather patterns of a garden. Temperatures may be colder or warmer because of a proximity to hedges, buildings, water or cities. The closer a garden is to a city or large body of water, the warmer it is. Changes in elevation and the location of a garden in a valley create microclimates that produce different weather patterns. Pockets of protection allow gardeners to grow plants that should not survive in their area. This growing “out of the zone” has tempted many a gardener at the garden center who spots an exciting new plant just off the truck from a balmy southern locale. Gardeners should be encouraged to look for hardiness zone information and then find microclimates to grow plants if they want to push their zone boundaries; the challenge is addictive but beware there’s a gamble in doing so – you will know the answer after the first unseasonably cold night. Always look for the hardiness zone so you can know where best to position your new garden plants. So what is causing this heightened interest in hardiness zones?

The Newest Hardiness Map

Early in 2012 the USDA released a new plant hardiness zone map, exciting news for gardeners and growers. The plant hardiness zone map is particularly helpful in deciding which plants will survive in a particular area. The latest USDA hardiness zone map is based on the average annual minimum winter temperature using weather data collected over 30 years from 1976 through 2005. Even though thirty years of data was used to create the new map, it is important to note that the map does not use the lowest temperature for any particular location that has ever occurred. Meaning hardiness zones listed on plant tags or in books should still be used as guidelines.

About using this weather data, the USDA explains, “The longer period (30 years) of data was selected by the group of horticultural, botanical, and climatological experts who led the review of the latest revision as the best balance between smoothing out the fluctuations of year-to-year weather variation and the concept that during their lifetimes, perennial plants mostly experience what is termed ‘weather’ rather than ‘climate.’”

Like the older map, the newest version is divided into color-coded five degree F sections (13 zones in total further subdivided into “a” (colder) and “b” (warmer) regions) that identify annual minimum temperatures from –60 F to 70 F and illustrates this detail down to county-scale.

One new feature of the recently released map is an interactive option to simply type in a zip code and find the corresponding hardiness zone and temperature range. You can also click on your state (or part of your state as is the case with Texas) and a map will appear with more detail about your region. This is a nice quick reference for those that don’t want to browse the full map to find what they need. In addition, state, regional and national versions of the map can be downloaded from the internet. Check them out at

The New USDA Plant Hardiness Zone map now defines 13 zones for gardeners with average annual extreme minimum temperatures from -60 F (-51 C) to 70 F (21 C).

New zones have been added (zones 12 and 13) for warmer regions in Hawaii and Puerto Rico that have extreme minimum temperatures above 50 and 60 F. Even though zone 12 plants will thrive outdoors in only these two locations, this information is important for many gardeners in colder areas to decide when to best bring these same plants indoors from the patio or garden when temperatures start to drop in the fall.

The longer period (30 years) of weather data used in the new hardiness map has resulted in most of the United States generally changing ½ zone (5 F) warmer (although some areas did change to colder zones because of the more accurate elevation depiction). The USDA says that this shift is attributed to more sophisticated mapping methods, and greater numbers of station observations, which has greatly improved accuracy (especially in mountainous regions), than from global warming.

Does this new map mean gardeners and growers will have to rip up their garden and change their plants if their hardiness zone has changed? Of course not. Plants that grew well up to now, will probably keep on growing just fine. What should be done as a precautionary measure is to carefully consider which plants are added to the garden if they are “pushing the hardiness zone boundary” and are not hardy enough for your location. But the hardiness zone map, while it is the most detailed one yet (down to the county level) doesn’t show microclimates that might exist in your garden or property. So look for sheltered spots on the south side of a building or evergreen windbreak if you want to try a few new plants that are not rated for your hardiness zone. Other cold weather strategies include putting on extra mulch, adding cut boughs to collect the snow, planting early so plants are well established and planting deeper. There are many factors that play into the hardiness of plants including light exposure, soil moisture, duration and timing of extreme cold, and humidity or plant moisture conditions.

One big difference shown on this new USDA map is the exclusion of Canada and Mexico which, although not as accurate as the U.S. portion on the old map, were still represented on one big North American map – making it easier to see where specific zones flowed over broader areas. The justification for not reproducing the USDA map like this again, they said, was that Canada has a more detailed map produced by Natural Resources Canada – Canadian Forest Services (see below).

The First Hardiness Maps

The first cold hardiness map was published in 1927 by Alfred Rehder in his classic Manual of Cultivated Trees and Shrubs. He used eight zones which were calculated based on the lowest mean temperature of the coldest month. The zones were marked in increments of 5 degrees F. Even with this information the boundary lines between zones were quite arbitrary. Donald Wyman in 1938 created a more accurate hardiness map. He used 40 years of data and based his map on the average annual minimum temperature. Surprisingly, his zones were created 5, 10 or 15 degrees F. apart. This lack of uniformity caused still another hardiness map to be developed twenty years later. In 1960, the United States Department of Agriculture (USDA) created its first map. The USDA map has since become the standard for the horticultural industry in North America. Most nurseries, reference books and catalogues use this map.

The Sunset Hardiness Map

Western gardeners came to feel that the USDA map was too restrictive with its cold temperature focus and didn’t reflect the true nature of the plant growing environments on the coast. So Sunset magazine created a climate zone map that took into account many more factors such as the length of the growing season, rainfall amounts (and timing), summer high temperatures (and winter lows), wind and humidity. Sunset’s map divides the country into 45 climate zones – most of which are located on the West coast. Going east and north, the zones become much broader. As an example, with the Sunset map, Florida is divided into just three zones; on the new USDA map this state shows seven zones.

The sunset map can be found at

A First Time Look at Heat Hardiness

An interesting alternative to the cold hardiness maps that have been developed for over 60 years, and of interest to southern gardeners, is the AHS Heat Zone Map. This map, first published in 1997, was created to indicate the frequency of high temperatures. The map is divided into 12 zones which have been determined from weather records. Researchers used the average number of days per year that the temperature is above 86 F to create their map. The map shows locations that have less than 1 day above this temperature to those locations that have over 210 days. Data for the map came from the daily maximum temperature records of 7,831 weather stations from the years 1974 through 1995.

Unfortunately the heat zone map is just for the US (including Alaska and Hawaii).  It was created because cold temperatures are not the only weather factor that affects the survival of plants. In general the nursery industry has placed a greater focus on cold tolerance and breeding cold hardy plants than on heat tolerance. There are many plants that will not tolerate being grown where they do not get adequate cold temperatures in the winter. Eastern Hemlock will not do well south of zone 7, and white spruce will grow poorly if planted in zones higher than 6. It has been found that high temperatures kill plants slower than cold and are more likely to be misdiagnosed. The AHS Heat Zone Map can provide valuable information to prevent this.

Take the plant zone information presented on the maps, printed on nursery labels or published in books as a guideline only. It is important to realize that hardiness is based on more than weather records of average minimum or maximum temperatures. Soil types, exposure, rainfall, humidity, proximity to windbreaks, soil moisture, snow cover, winter sunshine, plant types and the age of plants all contribute to survival ability. Also add one more criteria to your choice of hardiness map, which map is most accurate for your location. There are some good choices for gardeners, check them all out. For cold hardiness: USDA, Sunset, or Natural Resources Canada or for heat tolerance, the AHS heat zone ratings.

Canada’s Hardiness Map — Combining Climate Data with Indicator Plants

Canada has a hardiness zone map that was created by Agriculture Canada in 1967.  It is reputed to be the most detailed for Canadian latitudes.  Some people debate this statement and contend that the USDA map is better. The map was revised by Natural Resources Canada in 2000 using weather data from almost 30 years (1961 to 1990).

The map uses 9 zones to mark the hardiness of the most populated areas of Canada with 0 being the coldest and 8 the mildest (warmest). Each zone is divided into “a” (colder) and “b” (warmer) sections. The Canadian zones are not the same as the USDA zones. Canada plant hardiness zone 6 ? USDA zone 6. The Natural Resources Canada map has the added benefit of having indicator plants (trees and shrubs) that are representative of each zone – a helpful feature for gardeners.

Zone 1 Saskatoon Serviceberry (Amelanchier alnifolia)

Zone 2 Siberian Peashrub (Caragana arborescens)

Zone 3 Staghorn Sumac (Rhus typhina)

Zone 4 Ginkgo (Ginkgo biloba)

Zone 5 Early Forsythia (Forsythia ovata)

Zone 6 Japanese Maple (Acer palmatum)

Zone 7 Sweetgum (Liquidambar styraciflua)

Zone 8 Japanese aucuba (Aucuba japonica)

The map authors used a formula that takes into consideration several meteorological factors affecting the cold hardiness of a plant.  The most important being the minimum temperature during the winter.  They also considered the frost-free period, summer rainfall, maximum temperatures, snow cover and winds that would affect a plant’s growth.

Natural Resources Canada has taken on an additional project “Going Beyond the Zones” to expand the indicator plants beyond just trees and shrubs to include perennials as well. They want to develop a climatic profile for each plant using continent-wide mapping.  They have asked for help from gardeners across Canada and the United States to identify plants from a comprehensive list that will survive at their location. Once enough data is entered online, a range map will be generated (and updated when additional reports are submitted).


Native Plants for All Gardens

The use of native plants is becoming more and more prevalent in our landscapes. It is hard to argue against the use of these plants when many have such desirable attributes as drought tolerance, low maintenance and the ability to attract birds and other forms of wildlife. Now with local suppliers the ability to obtain plants for the garden is much easier. An added benefit is the fact that some native plant nurseries, such as Sweet Grass Gardens, in Ontario Canada will harvest seed from the local area to produce their plants. This strengthens the indigenous plant colony and does not introduce competing foreign diversity.

Many native plants have the ability to tolerate adverse weather and poor soil conditions because they naturally have genetic characteristics to withstand this environment. Many native plants have a very extensive root system to search out moisture and soil nutrients. Some plants have 2/3 of the plant underground. After a meadow planting of native wildflowers is established, the only maintenance needed is mowing once a year in the spring or burning it in late April (if permitted). Compare this to the number of times a lawn was mown last year!

Establishing a meadow or prairie garden entirely comprised of indigenous native plants is not a short term project. Re-establishing a landscape to its original state takes a dedicated effort and patience. This is a long process that will take between five to eight years to achieve the desired finished landscape. The proliferation of naturalized European weeds has made this task a longer and bigger challenge than it could have been. The project requires that all undesirables be totally removed before replanting or seeding can begin. Wise advice is to dedicate a whole season to soil preparation. Herbicide application, tillage, or a smothering fabric may be necessary. This starting-over process is necessary to introduce the right plants or seeds. The fall of the first year is ideal for seeding native plants. Native plants are classified as “cool season” plants and have the ability to start growing early in the spring before “warm season” weeds germinate. The spring of the second year is the preferred time to install grown plants. Delaying establishing the garden could mean another crop of “weeds” sprout. When selecting the plants for a native prairie garden, choose a ratio of 50% flowers and 50% grasses to produce a stable colony. In these groups, a minimum of four species of grasses and twelve species of flowers should be selected. To have a full season of interest choose at least four spring, four summer and four fall-blooming plant types.

For gardeners with moist or wet sites, several native plants can be grown effectively that naturally habit this environment. The tallest on the list and a butterfly attracting plant is Joe-pye-weed which reaches over six feet (two metres) and has a delicate pink flower. A relative is boneset (Eupatorium perfoliatum) which is shorter and has a very attractive white flower. Turtlehead and cardinal flower are highly recommended for wet locations along ponds or streams. The native shrub called button bush also attracts butterflies and can be grown in standing water. The flowers on this plant look like golf balls on short stalks.

Many gardeners have clay soil to cope with in the garden. Ken Parker of Sweet Grass Gardens suggests that clay soils should not have to be amended. With the proper plant selection, clay soil can grow satisfactory plants. He recommends only loosening the soil. Gardeners working with clay soil should consider the following plants. Rattlesnake Master (Eryngium yuccifolium) has yucca-like foliage with a white spiky flower. The flowers also attract butterflies. The cup plant (Silphium perfoliatrum) is named for an interesting characteristic. The leaves clasp the stem and create a reservoir for birds and butterflies to drink trapped water. The cup plant is over 6 feet (two metres) tall and should be at the back of a planting. The compass plant (Silphium laciniatum) is related to the cup plant and is also great for clay soil. The compass plant is named for the tendency of having lower leaves that point north and south. It might be worth growing this plant just to see if this is true. The best butterfly plant for clay is the yellow coneflower (Ratibida pinnata). The flower petals droop on this 60 cm plant. Prairie vervain (Verbena stricta) is a dry prairie plant that can be grown in droughty clay soils. Black-eyed Susan (Rudbeckia hirta) is a tough, durable plant that is very adaptable. It is tolerant of moist to dry locations that are in full sun to part shade. Black-eyed Susan’s can be introduced into the garden successfully either as plants or seeds. The last suggestion for a group of plants that grow and flower well in clay soil are the many species of fall-blooming asters.

Preparing the Gardener for the Garden

The light breeze, blue sky and plenty of sunshine are inspiration to tackle any job outdoors. Get ready, set, and go! The gardening season is soon upon us in full swing and the urge to be outside in the garden is strong. Heed a warning for over-exuberant gardeners who like to jump in with both feet (and arms and hands). Before starting your work – prepare the gardener for the garden. The consequences of over-exertion can be quite painful and result in a dimming of the gardening spirit. An entire medical encyclopedia could be filled with the consequences of gardening. They include: blisters, strains, sprains, sore muscles, sun burn, back injuries, allergies, cuts and scrapes, rashes, hearing loss, eye damage, and broken bones. Most of these can be avoided with a few precautions.

An inspirational garden near Philadelphia.Get ready for the physical exertions of gardening by doing some warm-up activities. This is particularly important for gardeners who have spent the winter watching Rosemary & Thyme episodes on DVD. The mind may be stimulated but the body probably needs attention to be in top form.

One of the first activities in the garden this spring is pruning. This could be pruning the roses, summer blooming shrubs, clematis, or low-growing evergreens. Pruning requires considerable gripping strength to sever large branches. To strengthen hand muscles for future pruning jobs, try crushing pop cans with your bare hands (watch for sharp edges), squeezing a tennis or stress release ball, or squeezing exercise grips. All of these exercises require force to be applied to a resisting object. This will strengthen your pruning hand muscles.

Some pruning jobs require the use of tools to be held over your head. This position puts strain on the neck and shoulder as well as the arm muscles. To build up strength for this task try washing windows that extend over your head. A hearty series of waves will also work.

Trimming hedges is another form of pruning. This task requires a different set of muscles than hand pruning or over-the-head pruning. Hedge trimming requires gardeners to hold heavy hand or electric shears for long periods of time. The shears must be moved with skilled accuracy or the hedge will be filled with unwanted dips or bows. To build up strength and trimming skills, hold a heavy book with arms outstretched and move it up and down from waist to head height. An alternate exercise is to wash windows with a squeegee. Keep the squeegee at arms length to clean the window. If hand shears are the only tool used for hedge trimming – build up arm muscles by clapping vigorously.

An Amsterdam CourtyardThe task of pushing a heavy wheelbarrow puts considerable strain on neck and shoulder muscles. These muscles are bearing a large downward force. To reduce this downward force, try to balance most of the weight over the wheel. This will also make the wheelbarrow easier to push. Gardeners can prepare for this strain by carrying equal weights of heavy grocery bags in each hand. As an alternate exercise, gardeners can carry two paint cans, water containers, bags of milk, etc. The key is to get an equal weight for each hand and have the force straight down.

The lawn will soon be growing very vigorously and will require frequent mowing. Pushing a lawn mower through thick turf can be a strenuous workout. Two sets of muscles bear most of the work. They are the ones in the shoulders and legs. To strengthen these muscles try some push-ups against a wall and a brisk walk around the block. When mowing, wear padded bicycle gloves to protect your palms from vibrations and blisters.

Weeding is a tough activity that could result in aching legs and back. Removing weeds by hand requires considerable squatting. This need to keep a low profile is often painful over time. The best advice is to avoid this position if possible. Use a long-handled hoe to remove the weeds and a fan rake to pick up the plant remnants. If hand weeding is unavoidable, invest in a kneeling stool to take pressure off your legs. Most kneeling stools can be used as a seat or a kneeling bench depending on their orientation. Long-handled hand tools will allow for a greater working area from the kneeling bench.

An Austin, Texas gardenDigging with a shovel or spade is one of the most strenuous tasks in the garden. This activity has an impact on the back, legs, arms, shoulders and hands. The most important advice for gardeners is to take it easy. Dig for a short period of time and then change to a less strenuous activity. Return to digging when you feel rested. Take increasingly larger loads as stamina is being built up. Do not over-exert yourself or injury may occur.

Lifting heavy objects is one of the most frequent causes of injuries to gardeners. Lifting affects the back, neck, abdominal and leg muscles. Common-sense advice says to lift with your legs and not your back. Unfortunately, this requires concentration (and re-training) for most people to accomplish a safe lift. Most people find that it is much easier to lift using your back than with your legs. Practice lifting a small object from the floor and place it on a table. Consciously tell yourself to use your legs while lifting. The next exercise is to keep your back straight and to hold the object close to your body. Do not twist when picking up the object. Use positive self-talk to adopt safe lifting techniques every time you lift.

Tender hands need protection during the beginning of the gardening season. The more that hands are used to handle rough materials, the faster they will build up callused areas. These calluses are protection from minor skin damage. Until the calluses (or thickened skin) are present, hands are susceptible to painful blisters, cuts or scrapes. Wear leather or cotton gloves to protect soft hands until they are toughened. Rose pruning and leaf raking are particularly damaging to unprotected hands.

An Amsterdam window boxWear gloves and long sleeves when working with roses, compost, sphagnum moss, soil and hay. These living and decaying plants are the host to a fungus that could cause an infection called Sporotrichosis. The fungus usually enters through a small cut or scratch on the hand. After several weeks (from 1-12) a small red bump forms at the wound site. This enlarges into an open sore. If untreated, the symptoms may come and go for years or travel to other more serious areas of the body and cause death. The cure rate is high for individuals that have good immune systems. Gardeners, nursery workers, florists, timber workers, and farmers are at the highest risks of contracting this disease. It is somewhat rare, but it can be misdiagnosed. As gardeners we should be aware of this disease and the possibility of infection.

A well-prepared gardener will tackle the upcoming gardening season with ease and enthusiasm with a little preparation beforehand. See you in the garden!

There’s More Than One Way to Recycle that Christmas Tree

The Holiday PartWinter Rose Poinsettia at Longwood Gardensy’s Over Now What Do I Do With the Tree and Poinsettias? 

The second week of January means that holidays are finished and life is slowly returning to a daily routine.  The last three weeks saw Santa find his way down the chimney, the year 2011 arrive with a bang (thankfully only from fireworks) and holiday decorations find their way back into big red and green storage boxes destined once again for the far reaches of the attic or basement.  What is left behind?  Maybe it is the loaf of dark fruitcake being used as a doorstop, or possibly a stack of cards and leftover wrapping paper, some fading poinsettias, or a shedding spruce tree. To make a clean start, it is time to deal with the “leftovers” and move on.  First the fruitcake. Toss it, bury it in the freezer for another eleven months, or lace it with a lot of Caribbean rum to make it edible.  Stash the cards away to use as labels for your next set of holiday presents or donate them to a primary school for craft work. 

The next item to deal with is a tree that is becoming a bigger and bigger fire hazard as it loses more moisture each day.  A sensible idea is to recycle the object of our holiday joy into a gardening product that will save us work.  Recycle your live Christmas tree into a wood chip mulch or use the branches as extra protection in the garden! 

The best trees to use as boughs in the garden are those that still have the vast majority of their needles adhering to the branches.  These boughs when placed in the garden, will trap air below them acting as great insulators.  They will also collect snow (another insulator).  Most areas have not come anywhere near our potential low temperatures so far this winter. Brace yourself for more cold temperatures.  It is still not too late to add more protection to the garden.  Every effort will help.  A few preparations and tools are needed before starting the job.  A small, curved, hand, pruning saw can be used to quickly sever the limbs from the trunk.  The tree could still have significant amounts of sap under the bark.  This sticky material will be a nuisance to remove from your hands and could be impossible to remove from clothes.  Thick, leather gloves will protect your hands from contact.  To protect your clothes, consider wearing your oldest, most worn out or least favourite jacket and pants you have.  When the job is finished, the bare trunk can be stored for future use as a natural stake or wildlife perch.  It would be fun to see it next season with an annual morning glory vine growing up it. 

The alternative to dismembering your tree is to send it to the chipper.  Many areas have special Christmas tree curbside pick-up dates during this week and next.  Christmas trees are collected and run through a powerful chipping machine that grinds them into small pieces.  The entire tree is used and the result is a combination of small disks (chips) of wood, cut up sections of twigs and loose needles.  This Christmas tree wood chip mulch is excellent for use under rhododendrons and azaleas.  These plants and many other acid-loving plants need a modified soil pH and have a shallow root system.  The wood chip mulch is dense enough so that it will slow the evaporation of water from the soil.  It will also help to stop weeds from germinating by blocking sunlight from reaching the soil.  The needle component of this mulch will contribute an additional benefit.  As the needles break down they will act to slightly acidify the soil.  The particle size is not as large as “bark mulch”, which can be purchased at most nurseries, and as a result Christmas tree mulch will not last as long.  It will though, last for more than one season in most cases and can be replenished next year at this time.  The decomposition process can be slowed if the mulch is applied in thicker layers.  For the best results apply the mulch at least 2 inches (5 cm)  in depth.  Thinner than this amount and the effects are diminished significantly.  Many cities will let homeowners take home a container full of wood chips in exchange for dropping off a tree to chip.  Bring your own sturdy container, shovel and shoveler for this task.  Trees should be free from decorations that do not decompose.  This includes tinsel, garland and lights.  Plastic tree bags used to capture shedding needles can be kept on the tree until it is unloaded and then removed. 

Are you dreading that your poinsettia will be hanging around until Easter? Is it time to make the decision about the destiny of this plant?  During its glory days it was vivid and fresh.  Now the colours are fading faster than a summer tan, and the leaves are dropping faster than a maple in fall.  The compost pile beckons.  Go for it. 

For those gardeners who insist on preserving every living plant that comes under their care-think twice about trying to rebloom poinsettias.  These finicky plants require lots of “proper” care, dedication and a certain amount of luck. Yes, the largest poinsettia grower in North America acknowledged that it is not an easy task.  If you are determined to master growing poinsettias in the home- here’s the details.  When your plants have started to look bedraggled, cut them down to 20 cm in height.  Continue to water your plant regularly and feed it with an all-purpose houseplant fertilizer.  New growth should have started by the time your poinsettias go outdoors in early June.  Transplant them into the next largest sized pot and sink them into a sunny location in the garden.  Continue watering  and fertilizing them regularly.  Pruning may be necessary to keep the plants to a compact size.  The key to getting poinsettias to bloom for the next Christmas is the day-length.  The bracts turn colour in response to an increase in the length of darkness.  The plants need total darkness at night, starting October 1st, to mimic natural light cycles.  To achieve this in the house, move the plants into a closet each night or place a large cardboard box over the plant.  Total darkness is needed for 14 hours each night without exception.  Another requirement for flowering is to keep the temperature between 60 and 70 degrees F. (18 and 21 Celsius).  Is this 10 week rigorous schedule worth the effort when a beautiful, full poinsettia can be purchased for a very reasonable amount next December? Hmm ask me in 10 months.

The Christmas tree recycling bin image above from Place Vosges, Paris, France is used courtesy of Wikipedia creative commons license.

Poinsettias – Symbols of the Holiday Season

Winter Rose Poinsettias at Longwood Gardens

Winter Rose Poinsettias at Longwood Gardens

It just wouldn’t be Christmas without the poinsettia. And in case you have forgotten your poinsettia facts since last year here’s a refresher on what you need to know about this festive plant.
Whether poinsettias are in the traditional velvety red color or any of the new streaked, spotted or dyed forms of plum, peach, blueberry, orange or cranberry colors, these plants help set the stage for a great holiday celebration.
For all the cheer that poinsettias bring, there are still some people that look upon this festive plant as poison. Stop, let it be said up front — poinsettias are not poisonous! This myth started almost ninety years ago in Hawaii and amazingly still continues to this day. Apparently an Army officer’s two-year-old child died after supposedly eating a poinsettia leaf. The Physician who made the diagnosis later realized he had identified the wrong plant. He had planned to return to the mainland to correct his error when he suddenly died (unrelated to poinsettias) and the story spread and spread. Although it was later determined to be a case of incorrect plant identification, many people still believed that poinsettias are poisonous.
As recently as 1995, sixty-six percent of people surveyed by the Society of American Florists believed that poinsettias were poisonous even though there was a lot of evidence to disprove this myth. Researchers at Ohio State University tested the effects of ingesting high doses of leaves, stems and sap and found the plant non-toxic.
In the United States, the POISINDEX database has extrapolated evidence from experiments done on animals that suggest that a fifty-pound child could eat 500 or more poinsettia leaves with no ill effects. This was the limit of their testing. A survey of United States poison control centers in 1995 resulted in no reports of toxic reactions involving poinsettias. This seems like an overwhelming amount of evidence to support the non-toxic nature of the poinsettia.
Many families with small children still shun this plant because of the advice passed down through the generations from friends or relatives. Perhaps it is because the name “poinsettia” sounds a lot like “poison”. The plant is not entirely harmless, though. Some people develop a rash if the milky sap comes in contact with their skin. On the positive side, poinsettias have been included on a list of plants that clean indoor air.
Even with the myth about poisonous poinsettias, they are a $200 million per year business in the United States. Of the millions of plants sold, red is the most favorite poinsettia color. A whopping seventy-four percent of poinsettias are sold in this traditional holiday color. This figure has actually gone up recently (but is still down from a high of 80%). Trailing at a very distant second is the color white. It is followed by pink, marble and then jingle bells (pink with white splashes).
Poinsettias are named after Joel Roberts Poinsett, who was an avid botanist and also the first United States Ambassador to Mexico in the late 1820’s. Most people believe that Poinsett discovered the poinsettia when travelling on Christmas Day near the Southern Mexico city of Taxco. The bright red plant was believed to be decorating the nativity scene in a church he visited.
In 1828, Ambassador Poinsett exported the bright red holiday plant to his own greenhouses in Greenville, South Carolina where they were propagated and distributed to his horticultural friends. The plant steadily gained popularity. Today, over fifty-two million poinsettia plants (of 100 different types) are sold in the United States. This exceeds the annual sales of all other flowering potted plants combined. Poinsettias make a very good landscape plant in frost-free areas and can be used as an interesting cut flower.

Poinsettias on display at Longwood Gardens (2006)

Poinsettias on display at Longwood Gardens (2006)

The poinsettia was first called Euphorbia pulcherrima in the botanical world. It was named by a German taxonomist in 1833. Literally, the botanical name means “the most beautiful Euphorbia.” In Florida this plant grows up to five feet tall and naturally blooms every December. It is hardy to zone 9 and will only grow outside year-round in the most southern regions of the United States.
Interestingly, it is not the poinsettia flower that is so colorful. The flowers are the small yellow “buds” at the very center of the plant. A young plant still has these flowers intact. The famous poinsettia color is really from petal-like bracts that are beneath the flowers. Bracts are modified leaves that are associated with a plant’s flower. The bracts change from green to the brilliant colors in response to temperature and day length.
What does a healthy poinsettia look like? It should have healthy leaves down the stem to the soil. Poinsettias drop their leaves when they have been shocked by a cold draft. A thick, sturdy stem is another sign of a well-grown plant. The bracts should be a deep, rich, intense color that is not greenish or faded. Finally, look under the leaves for white flies. These small insects are a prevalent problem and are attracted to poinsettias (among other plants) like a magnet.
The number one tip to care for poinsettias is to avoid extremes! This includes providing protection when taking your plant home. Once home, keep your plants away from extremes of hot and cold temperatures. The right temperature for a poinsettia is also a comfortable one for humans including a humidity level that is about 30%. Bright, indirect sunlight is best because a strong sun on the bracts could fade their color. When watering, keep the soil moist but not too wet or too dry. Let the soil dry out between watering so that it feels slightly dry to the touch. The newer varieties of poinsettias are much more durable and are far less finicky. Prestige is a deep red poinsettia that is reputed to be the toughest poinsettia offered by North America’s largest poinsettia grower. This one will probably be around long past the holidays.
Christmas at Longwood Gardens (2006)What’s available besides red, white and pink poinsettias? If you are not a traditional poinsettia lover or want to try a different color this year, look for cream (plus rose and pink colors), peach, striped, marbled, purple, variegated foliage, peppermint twist, eggnog and winter rose (twisted bracts now in marble, pink, deep pink and dark red colors) or spotted (such as Shimmer or Jingle Bells) plants. New is the Polar Bear poinsettia from the Ecke people who are donating 5% of the net sales revenue to Polar Bear International. The light creamy white color of the poinsettia matches the majestic polar bear. And if you like your poinsettias shockingly non-traditional, try the dyed and glittered blue, orange, purple or pink. The advantage of having non-red poinsettias in the house is that they don’t look quite so out of place at Easter.
What’s new for next year? With growers making plans for next year’s crops, the news is out that your poinsettia future might include Red Glitter (deep red bracts with white streaks and glitter).
December 12th is a special day for poinsettia fanciers. It has been declared National Poinsettia Day. This day is to honor Joel Roberts Poinsett, the man who started it all. Decorate your house with color this holiday season and bring home poinsettias.
My favorite? I have long had a fondness for unusual natural colorations of poinsettias and my current favorite is Monet Twilight. It is a unique multi-colored poinsettia with cream, rose and pink bracts.

Enjoy the season! Best wishes to all.

Cold Frame or Hotbed – Extend Your Growing Season With a Simple Structure

Cold frames (or hotbeds) are simple structures that have two main purposes, to act like miniature greenhouses to trap radiant heat and to provide protection and insulation from the elements. Cold frames traditionally have a sloped top that is positioned for maximum sun exposure, lift off or slide open sash (lids), insulated side walls that sit on the soil surface or are excavated below ground. Cold frames and hotbeds differ only in that one is heated and the other isn’t. Both types are useful in the garden — particularly from fall through spring to protect plants during cold or stormy weather. They are handy for extending the growing season and to provide a warm, sheltered area to ripen tomatoes longer into the fall or winter, to start cool weather crops (lettuce and leafy greens, radish, peas, cabbage, and more) earlier, or in some locations to overwinter forced bulbs, root vegetables, or hardwood cuttings. Many cold frames have the advantage of being temporary and portable too. Some gardeners profess that their cold frame extends their growing season by 4-6 weeks in spring and fall.

Cold frames differ from root cellars because they are designed to keep plants growing, not just for cold storage. They have no supplemental heat but rely on solar thermal energy for warmth. The design of the sloped wooden outer frame collects and traps heat from the sun. With a purpose to protect plants, most cold frames will keep plants one hardiness zone warmer (about 10 degrees F.) and work well to extend the season. Cold frames are great for getting an earlier start in the spring (especially when growing shorter, cool weather plants such as pansies, dusty miller, primroses, dianthus, dwarf snapdragons, cyclamen and ornamental cabbage), hardening off young plants in the spring or to keep root crops longer into the winter (instead of using a root cellar).

Hotbeds are cold frames that have the addition of a heat source (usually either mechanical or biological). Hotbeds are used for the same purposes as cold frames with the addition of being a good site to propagate woody cuttings which root faster with bottom heat. Hotbeds can have electric heating cables installed in the base substrate or use somewhat fresh manure for warmth.

Cold frames can be easily made from recycled materials and cost almost nothing for the materials, or an already manufactured version can be purchased for $100-$500. Do-it-yourselfers with access to 2 x 6s, 2 x 8s or 2 x 10s and window sash can easily construct a cold frame.


Cold frames and hotbeds can be located using the same principles. A southern exposure is beneficial so cold frames and plants can get the most benefit from sunlight. A west-facing direction is the second best orientation. A solid (or mostly solid) windbreak on the north side, which doesn’t cast any shade on it, will create an even warmer microclimate for the cold frame. If a close windbreak is not available, bales of straw can be used on the north side wall for temporary added insulation.

Site your frame near the house for easy access and attention. Pools of water in the vicinity of the frame should not sit for long periods during the fall, winter and spring. Good drainage is beneficial for plants. An accessible (summer and winter) water supply (and electrical outlet if needed) should be a consideration for locating a cold frame.


Most cold frames are a simple rectangular box, about 2-3 ft high that either sits on the soil surface or can be sunk into the ground. The sloped front faces south or west and is angled at about 1″ per foot (about a 6-8″ difference from top to bottom or 35 to 55 degrees). The angle will vary depending on whether the cold frame is to be used in the winter. The higher the angle, the more sun will enter the frame during the winter when the sun is lower in the sky. One simple formula is to add 15 to 20 degrees to your latitude. Another consideration is the equipment available to make the angled cuts. In some cases a standard 45 degrees will be perfectly adequate.

The frame height depends on what the cold frame is being used for — but to get the best angle for the sash, there isn’t much opportunity to go much beyond the standard 18″ back (north) and 12″ front (south) frame heights. Within reason, you can make your frame taller if you will be mostly hardening off older plants or shorter for starting flats of seedlings.

Many different materials, both recycled and new can be used for the sash (frame lid). These include such options as glass, fiberglass, poly film or wooden snow fence. In many cases the size of the sash will determine the size of the cold frame — ok it’s just much easier this way.

Double glazed windows make good durable sash that are heavier than other materials. Glass is generally looked upon as the best material to cover a cold frame. Other materials include discarded storm windows from screen doors or no longer needed patio doors or bathroom shower doors.

If polyethylene plastic is used, the film should be clear and at least 6 mil thick. Consider using a double layer for extra insulation. The poly is not very durable and will probably have to be replaced each year.

Fiberglass or polycarbonate materials make very good sash for cold frames, although they are quite a bit more expensive to purchase.

Comparing Cold Frame Sash Material [Sash Material, Pros and Cons]


  • Recycled windows can be used.
  • Good light transmission.
  • Good insulation value.
  • More hail-proof (weatherproof) than polyethylene.
  • Glass is heavy. The extra weight means the sash and side frame must be able to withstand the extra weight.
  • Opening and closing involves additional weight.
  • Broken glass is more difficult to replace and repair.
  • Expensive to purchase.

Polyethylene film

  • Inexpensive to purchase.
  • Probably must be replaced each year.
  • Easy to install and lightweight to handle.
  • A double layer will provide more insulation. Won’t withstand large hail stones or heavy snow or ice loads.
  • Sash must be secured so that it doesn’t take flight in a strong wind.

Polycarbonate panel

  • Strong and durable. Will last many years.
  • Better insulation value when using double polycarbonate layer panels. Expensive to purchase.
  • Nonstandard sizes involve extra cutting.

Fiberglas panel

  • May lose good light transmission over time and become more opaque.
  • Expensive to purchase.
  • Nonstandard sizes involve extra cutting.

Wooden fence/lath

  • Easy to construct. Often used with polyethylene film to give added support.
  • Inexpensive.
  • Can easily be removed to ventilate. Not good insulation or thermal conducting without the addition of other materials.

Side Frame Materials

A wide range of materials can be used for the cold frame box. These include wood, brick, masonry, cinder, concrete blocks or metal pieces. The insulation value of each of these materials varies and should be a consideration when picking the best material as well as availability and handling ease. Straw bales can also be used to make a temporary cold frame using a couple of saw horses and some heavy plastic. Metal cold frames should only be used where minimal temperature protection is needed as they have very little insulation value and heat won’t be retained long.

Mostly cold frames have traditionally been made of wood. With this material they are easy to construct and can be dismantled, moved or expanded easily. Untreated wood is recommended (recycled or new) and home treated using a non-toxic wood preservative. If untreated wood is used, then the inside of the frame can be painted with a white latex-based paint to add more light reflection. Use a minimum of 1″ thick lumber (2″ will add greater durability, strength and insulation properties).

Seal all cold frame joints to maximize heat retention. Foamboard insulation can be used inside the frame on the above-ground, north-facing side for even more insulation.

Building a Hotbed

Cold frames can be turned into hotbeds through the addition of a heat source. Hotbeds have the advantage over cold frames because they are more consistent in their temperature and can be used for an even greater number of overwintering or season extending purposes. If a constant and accurate temperature is required, electric heating cables should be used in the soil under the plants. If this is the case, position the hotbed near an electrical outlet.

For less demanding heating needs other materials such as light bulbs, manure, hot water or steam can be used to heat the hotbed. Many people find that hotbeds are not needed and simply use passive solar energy to heat their cold frames. When doing this, black painted barrels filled with water absorb heat during the day and slowly release it at night.

Using Manure

When readily available, manure is a cheap and convenient heat source. Hotbeds can be made by placing the frame on a manure pile and mounding the material around the frame. This works best to extend the spring and fall season. Alternatively, a layer of manure 18-30 inches deep below the hotbed will provide a source of heat. Let manure sit for at least 10 days before using it in a hotbed. Place a 6″ layer of soil over the manure inside the hotbed to protect plant roots. Monitor the soil temperature and move plants into the hotbed only when temperatures are below 85 F. Hotbeds using manure must also have excellent drainage. Manure will stop fermenting (and stop producing heat) if it becomes soaked with water.

Extra Insulation

On unusually cold nights, loose straw can be piled on top of the cold frame sash to provide extra insulation if needed. A thermal blanket (purchased from a nursery or a cast off flannel sheet) is also ideal to put over the plants. This will trap the heat that accumulated during the day and keep the plants warm into the night.

Starting Seeds

Get a head start by growing tomato seedlings in a cold frame. Soil temperatures between 65 -78 F. are ideal for starting many seeds. To prevent seedlings from stretching and growing soft, monitor the temperature once they germinate and vent the frame if air temperatures are above 75 F. Many cool-season crops (lettuce, peas, cabbage, cauliflower, onions, etc.) are ideal for cold frames and can be started much earlier in the spring. The frame though must be checked regularly and may need venting on bright, sunny days.

Venting a Cold Frame

Cold frames are designed to be quite versatile in their venting options. Depending on the amount of venting required and the direction of the wind, the sash can be propped up, slid up, pushed down or removed entirely to provide good air circulation. In many cases, when outside air temperatures reach 60 F. the interior temperatures are high enough to warrant venting – even if it is lifting the sash a few inches at the bottom to let the heat escape.

If other commitments don’t allow for frequent temperature checking of the cold frame so plants inside don’t get overheated or chilled, several models of automatic vent openers are available to purchase and install. These can be set to open and close at specific temperatures. Many have pneumatic cylinders that respond to temperature changes and gradually open the sash in increments as the temperatures rise. These start at about $50. No external power is needed for many of them and the automatic openers lift up to 12 pounds in weight up to 17 inches in height.

Best vegetables to grow in a cold frame.

Root crops: beets, carrots, parsnip, rutabaga, onions, leeks, kohlrabi

Leaf crops: Brussels sprouts, cabbage, cauliflower, radish, Swiss chard, kale, collards, lettuce, mustard, spinach, mâche/corn salad, scallions, kale

Cold frame diagrams can be found at the following websites:

Originally published in the Acres U.S.A magazine, September 2010 issue.

Fall Rains

Let the Rain Fall

Our recent deluge of rain seems to be taking revenge for all those beautiful clear, sunny days of the previous summer. Being rain-free for so many days was a joy for gardeners, golfers, travellers or anyone wanting to spend time outdoors. Now we are all paying the price as low-pressure centers hover overhead and drop liquid precipitation on our gardens. As much as we complain about our dislike for the disruption and inconvenience of wet weather, it does have some benefits for plants.

Water is great in the fall to give broad-leaved evergreens a better chance of making it through the winter (alive and preferably also healthy). Broad-leaved evergreens are the plants that keep their leaves all year round (under normal circumstances). Hollies, euonymus, boxwood, cotoneaster, English ivy, kalmia, mahonia, pachysandra, pieris, pyracantha, rhododendrons, and vinca all fit into the general classification of broad-leaved evergreens. These plants are popular because they have a different look in the garden than the narrow leaved conifers. They also add much needed visual interest in the garden during the winter. Broad-leaved evergreens do need some extra protection during the winter from the damaging effects of sun and wind. Fall rains can provide some of this protection. During the winter, broad-leaved evergreens are constantly loosing moisture to the air. This moisture cannot be replaced once the soil is frozen. Bright sun and strong winds cause more moisture to be lost than normal. The result is winter burn or sun scorch, which causes the leaves to turn brown around the margins and sometimes progress inward. If plants are well stocked with water in the fall, then there’s a greater margin before damage is done.

Rainwater in the garden also helps speed up the composting process. An ideal compost pile should be as damp as a wrung out sponge. This moisture plus frequent turning and the appropriate ratio of carbon (browns) to nitrogen (greens) hastens the composting process. Watch out for too much water (or rain) when the whole composting process could turn into a smelly anaerobic decomposing mess.

Rainy days keep most gardeners out of the garden. This lets gardeners focus on other important aspects of their life (like spouses and offspring). In October when it is more likely to rain than not, the weather allows for regrouping indoors. This time could be used to make plans for the excess vegetables waiting to be harvested. Some of these are always all those unripe tomatoes. Incidentally, being inside during the rain is a great time to surf the Internet and read garden blogs.

A dreary, grey day full of rain is the best time to venture outside and see the fall colours. This type of weather brightens and intensifies the colours of the trees. The view out of a rain-smeared windshield also adds to the atmosphere. Here vivid yellows seem to glow and scarlet colours shimmer more in the rain. The glossiness of the wet leaves upon closer inspection adds another attractive feature.

To gardeners, nitrogen is one of the most important nutrients for plants to keep them happy and healthy. Nitrogen results in larger plants and increased yields. It is one of the macronutrients that need to be replenished the most in the soil because some nitrogen leaches (washes) away with the rain. Ironically, one handy supply of nitrogen is courtesy of the stormy clouds overhead. Some of the nitrogen in the soil comes from lightning in the air that travels with the rain droplets.

Cleome (spider flower) after the fall rain at Temple

Cleome (spider flower) after the fall rain at Temple

The air is naturally full of nitrogen. In fact 4 out of every 5 molecules in air is nitrogen. Unfortunately, this form of nitrogen is not much use to plants. The mystery of how nitrogen in the air is changed into usable nitrogen in the soil involves the heat of lightning. Lightning heating up the air forces nitrogen gas to bond with oxygen. This creates nitrogen oxides. These mix in the air, dissolve and fall out with the rain landing at plant roots as a usable form of nitrogen (called nitric acid). Lightning produces a small percentage of the total nitrogen oxides around the world. Cars and power plants that burn fossil fuels produce the bulk (a cause of acid rain).

Lightning does not have to crack overhead to bring nitrogen to the garden. Lightning in the vicinity will spread out and land throughout the neighbourhood. Every day lightning strikes the earth over 8 million times somewhere around the surface of the planet. Interestingly, one good lightning storm can supply between three and ten percent of the recommended year’s supply of nitrogen for the lawn. More than ten storms during the summer and the lawn may not need any commercial fertilizer.

Rain is great for cleaning off the dirt that the wind picks up and deposits on plants. This layer of dust is easily removed with a steady or heavy rain. The plants look better and they will grow better if dust is not clogging their stomata (breathing pores). Stomata are found on plant leaves and are an important opening for gas exchange to occur.

Fall rains may also bring about some plant health benefits. Some plant pests are chased away by moisture on plant leaves. The two-spotted spider mite is one of these. It is at its optimum reproductive speed when temperatures are at 86 F. (30 degrees Celsius). At this temperature under dry conditions mites reproduce every eight days. In the fall when temperatures drop to 53 F. (12 degrees C.) and the rain is falling, the mite takes 6 weeks to reproduce. Rain is a great pest control measure for any plants that are bothered by spider mites.

Beyond Marigolds – Growing Seeds Part 2

Once easy-to-grow seeds such as marigolds are mastered, it is time to tackle plants that are a little more challenging.

Starting seeds is an extremely rewarding activity and even trying to germinate some of the challenging seeds can be very successful if a little research is done to find out which techniques should be used.

If certain basic conditions are met, most annual and vegetable seeds do not require special treatment to achieve a high percentage of germination. The seed, which must be viable and mature, needs a proper balance of environmental conditions (moisture, temperature, light and air). Some more challenging seeds have natural inhibitors to germination and require special treatment. Such inhibitors include: a small dust-like size; a hard moisture-proof seed coat; a reluctance to germinate until maturity; a chemical that must be leached away; or specific requirements of light or darkness. These seeds may seem like they require extraordinary efforts to get them to grow, but these protections are adaptations which ensure germination at an appropriate time in the wild. Once they are known, then they can be overcome.

Seeds that are a challenge to both home gardeners and professional growers will often have poor or maybe even no germination unless a strict regimen is followed. Such seeds need extra attention to germinating or growing temperatures, moisture and light levels. Otherwise they loose their viability very fast after harvesting. Begonia seed will be dust-like, if the seed is not coated or pelleted, and will be very hard to sow. It also needs extra light during the day from January through March to grow to a size where it can be planted in the garden in early June. The shade loving annual, Browallia needs to be started extra early because it grows very slowly. Dahlberg daisy has irregular germination. Eustoma hates cool temperatures and must be germinated at 77 degrees F. (25 degrees C.).  Start this plant early and sow it directly into deep pots to accommodate an extensive tap root. Madagascar Periwinkle must be keep warm and in darkness until germination is complete. Do not overwater it or subject it to cool temperatures or it will sulk. Osteospermum must be kept cool and dry. Verbena usually has poor germination rates that could be as low as 30%. Use fresh seed that has been chilled for 1 week. Water the seeding pots and soil the day before sowing but do not water them after sowing because the seed is susceptible to rot if moisture levels are high. Cover the seeding containers with black plastic and keep them at 25 degrees C. Chill snapdragon seed for several days before sowing. Soak morning glory seed overnight to soften their coats. Germinate melampodium & mimulus at a cool 65 deg. F. (18 degrees C.). African marigolds should be covered after germination with an opaque material from 5 pm until 8 am for the first 2 weeks to simulate short daylength and produce better flowering. Nasturtium do not need any more than a starter fertilizer after they have been transplanted or else lots of foliage will be produced at the expense of flowers.

Seeds that are very small, such as fibrous begonia, petunia, coleus, dianthus or snapdragons, are often available as pelleted seed. This process coats each seed to make them easier to handle, and germinate faster. The extra cost of these seeds is worth it. Do not cover these seeds when sowing. Simply press them gently into the soil. Small seeds that are not pelleted can be mixed with horticultural sand and sown straight from the seed packet. Tip the packet on its edge and gently tap it with a pencil. The seeds will march down the packet and can be sown evenly spaced in a neat line.

Seeds with a hard seed coat that will not absorb moisture must go through a process of scarification to achieve good germination rates. The trick is to gently abrade the seed coat without damaging the interior seed parts. Depending on the size of the seed and the thickness of the seed coat, a knife, file or sandpaper can be used to scarify. Small seed can be soaked for 24 hours before sowing. This will soften the seed coat and shorten the time for needed for germination. Plant these seeds immediately after soaking. Commercial seed suppliers will use a scarifying machine or apply an acid to wear down the seed coat. One advantage of seeds with a hard seed coat is that they have a long storage life.

Stratification is a process where seeds are subjected to moisture and cool or cold conditions in order to get them to germinate. This is necessary for seeds that are immature when they are harvested. Many perennials and woody plants fall into this group. To get them to germinate, seeds are mixed with moist sphagnum moss or a seeding media and placed in a sealed, clear plastic bag. This is placed into either the refrigerator or freezer as instructed. After the recommended time has elapsed, the seeds can be sown into a seeding container. An alternative is to sow the seeds directly into a seeding container, cover it with a clear plastic bag, label and seal it and then place the whole thing into the refrigerator or freezer.

One of the most problematic diseases that attacks seedlings is called “damping-off.” This is a fungus disease that could be lurking in the soil or on seedcoats. The disease can even move from one seed container to another by hitching a ride through the water. Damping-off strikes very fast and without much warning. One day your newly germinating seedlings are fine and the next day some of them have toppled as if they were severed by a miniature chain saw. There are several tips to keep this disease under control. Use sterilized soil with good drainage to start your seedlings. Sow your seeds so that there is some space between each seed – do not overcrowd them. Make sure that there is good air circulation. You may have to set up a small fan to gently circulate the air around. Avoid overwatering your seedlings. Sowing seeds into rows will help reduce the chances that all of your seedlings will succumb to this disease. If the disease appears, a row or part of a row can be removed to stop the disease from spreading. Commercial fungicides for damping-off can be used to control this disease.

Once seedlings have grown to a stage where they have their first or second set of true leaves then they can be transplanted into their own pot or cell pack. The true leaves will normally be the ones just after the first two large food storage cotyledon leaves. Transplanting seedlings will give them more room to develop and will help to ensure that they have a strong root development.

Soils used for transplanting can be of a different recipe than the seeding media. It is less critical that this soil be of a fine consistency, but it must still be sterilized. When selecting the new growing container, remember that the smaller the volume of soil that annuals have to grow roots, the faster they will develop.

Many plants are available as a collection of mixed colours. Some colours are not as strong as the others. When transplanting seedlings into their own container select a variety of sizes to ensure that all colours are represented. This advice is contrary to the natural tendency of selecting the biggest and strongest seedlings. If this is done, then there is sometimes a risk of increasing the percentages of certain colours.

Before transplanting, fill your new containers with soil and moisten it. Also moisten your seedlings. Next choose a thin narrow tool to help untangle seedling roots. A pencil, ice pick, thin bamboo stake, chop stick, commercially manufactured dibble, or similar tool will work. Label your new container with the plant name and date.

Images coutesy of and used under the creative commons license.

Sowing Seeds

Spring seems to arrive a little sooner when gardeners start their own plants indoors. Starting plants from seed is a very rewarding activity and there are many locations throughout the house suitable for starting seeds. The two critical factors are the amount of light and the soil temperature. Generally, a consistent temperature near 75 degrees F. (21-24 degrees Celsius) is ideal. This can be achieved on top of the refrigerator or on a heating pad. For adequate light consider the area under cupboards with fluorescent lights, a window sill, or on the floor of a solarium.

The first leaves of seedlings emerging

The first leaves of seedlings emerging

When should annual flower seeds be sown? Sowing dates are a little flexible because many factors have an influence on a seedlings rate of growth. These include light levels, day and night temperatures, fertilizer application, soil type, timing of transplanting, moisture levels, and seed age. The best advice is to use the dates below only as a guideline and make a chart that is specific to your conditions. The following sowing dates are determined by counting backward from the average frost date – in this case I have picked the first week in June. If you feel that it will be safe to plant annuals outside during the last week of May, then subtract one week. One of the fastest growing annual vines are morning glories which, if sown on May 1st, will probably be ready for outdoor planting within 4 weeks. Cosmos should be sown on April 18th, 6 weeks before planting outside. There are several annuals, such as amaranthus, sunflower, sanvitalia, and zinnia, that should be sown on April 12th. Annuals that require 8 weeks of indoor growing time should be started on April 5. These include melampodium, mimulus, nicotiana, marigold, and nasturtium. Brachycome, gomphrena, portulaca, and thunbergia are annuals that should be sown near the end of March. Annuals that require 10 weeks to reach a size where they can be planted safely outside are ageratum, celosia, cleome, annual phlox, and salvia. Sow annual dianthus, coleus, impatiens, and nierembergia indoors on March 15. Gazania, lobelia, petunia, and dusty miller require 12 weeks before they can be moved outdoors and should be sown in early March. Snapdragons, ivy geraniums, seed geraniums, and pansies are some of the slowest growing annuals and require 14 or more weeks before they can be planted outdoors. Start them around the middle of February. The slowest growing group of annuals includes begonia, browallia, and eustoma. These plants need to be sown in early February so that they can have 16 or more weeks to grow before being planted outside.

Starting seeds is addictive and can quickly fill up your light garden or windowsill. Finding space and containers is sometimes a challenge. The most important requirement of a seeding container is to hold soil. Commercial seeding trays can be purchased as a complete kit (full-sized or window sill version) which contains a water-holding tray, cell pack inserts, and a clear plastic lid. Gardeners don’t necessarily have to purchase new equipment for this project if they have some shallow plastic or clay pots handy. These can be used with a plastic bag to simulate a miniature greenhouse. Some gardeners who find they have more seeds or seedlings than pots or flats become very resourceful. They use margarine or yogurt containers, egg shells halved or styrofoam cups. All of these can make great seeding containers as long as they have drainage holes.

Tomato seedling

Tomato seedling

Soil is critical to the success of starting seeds. It must be sterilized, light-weight, and have a fine texture. It also must have a small nutrient supply, hold moisture, but also provide good drainage. The simplest way to meet these requirements is to purchase soil that is manufactured specifically for starting seeds.

Should seeds be covered? Most seeds will germinate well if they are covered with a thin layer of soil. This soil provides moisture and darkness which is required for good seed germination. Seeds that need absolute darkness should also be covered with a dark garbage bag to block all light. Upon germination, all seedlings will stretch looking for light. Check your pots daily for emerging green stems or roots. This is the beginning stages of germination. Change the dark cover to a clear plastic one if more than 40% of the seeds have germinated.

A small group of plant seeds must remain uncovered in order to germinate well. They require light to trigger germination. Some of the annuals that are in this group are: ageratum, begonia, brachycome, browallia, coleus, sweet alyssum, mimulus, nicotiana, petunia, portulaca, salvia, dusty miller, and torenia. When sowing these seeds, scatter them on the soil surface. Gently press them down into the soil so that they have good contact but are still exposed to the light. A clear plastic cover will keep the humidity high near the seeds and increase germination time.

A few annuals need to be lightly covered with soil to have the best germination results. They have to be as close to the surface as possible for exposure to light and they have to have a thin covering of soil to maintain humidity and moisture. Keep the soil surface moist. Some of the plants that should be lightly covered are: amaranthus, Madagascar periwinkle, cleome, dianthus, heliotrope, impatiens, melampodium, nierembergia, marigolds, verbena, and pansy.

For other annuals not listed above, check their seed packet or a reference book for instructions. Most likely they will be in the group that needs to be lightly covered.

Germination and growing temperature requirements are often different from one annual to another. In a lot of cases the minimum night temperatures are the critical ones. Refer to seed packets, seed catalogues or a reference book for information on what temperatures are ideal for optimum plant growth.

Some annuals don’t like to be disturbed – they resent being transplanted and will sulk. These plants should be sown into a bigger pot to reduce the amount of shock during transplanting. Some seeds can be sown into fiber pots to avoid disturbing them later since they can be planted outside while still in the pot. Eschscholzia, morning glory, nasturtiums, phlox, sunflowers, sweet peas, thunbergia, and zinnia should be sown directly into their final indoor growing container. Place 2-3 seeds in each cell or container and later thin the seedlings to a single strong plant.

A few other annuals produce plants that are too small to handle, such as portulaca and sweet alyssum. Several seeds of these can be sown into each final growing container. No thinning is needed in this case.

Proper misting and watering are important for good germination and plant health. Check the soil moisture level at least once a day. If a seed is allowed to dry out after it starts to soak up moisture, it will die. Use tepid (room temperature) water that has been allowed to sit for 12 hours. For delicate seedlings, a mister will gently apply water to the soil without causing injury from wash-outs or fallen plants. If pots or trays of seeds are very dry they can be placed into a laundry sink with a shallow amount of water. The pots will gradually soak up water from the bottom and the seeds or seedlings will not be disturbed. Once the top of the soil is barely moist, remove the pots from the sink and drain them.

Novice gardeners and children can have great success with starting seeds indoors by selecting plants that are easy to grow. Marigolds, geraniums (takes a long time), nasturtiums, sunflowers, morning glory (soak the seeds overnight), and sweet peas (rub the seed with sandpaper then soak the seeds overnight before sowing) are excellent suggestions.

Sow more seeds than you need for the garden. The average germination rate is between 60 and 70 percent, so plan to sow 50% more seed than you require as plants. If you end up with more plants than you can use, donate them to a local horticulture or gardening society or give them to your neighbours.

Extra seeds can be stored for next year in a sealed glass jar in the refrigerator. This helps keep the moisture levels high in the seeds. Remember seeds are living things. Viability will decrease at different speeds for each seed type. Some seeds can be stored for up to 5 years while others should be purchased fresh every year. Begonia, impatiens, onion, peppers, and viola have shorter storage viability than tomato, sweet pea and zinnia.

The transplanting process is very simple with two main rules. Never hold your seedlings by the stem. Use your fingers to grasp only the leaves in order to avoid causing serious damage to the fragile stem. Use your transplanting tool or your finger to create a hole in the centre of new container to the depth of your seedlings roots. Carefully separate one seedling from the rest and plant it into the hole. Plant it at the same depth as it was growing. Gently firm the soil around the roots to remove any air pockets. Once again, be careful of the fragile stem. The second rule is to water the seedling after transplanting. Then place it under a light garden or cover it for a few days if it is on a sunny windowsill.

First two images copyright, last two images courtesy of and used under the creative commons license.

Winter Weather and the Garden

Winter Garden Concerns

How is this unseasonably warm weather affecting plants that are trying to hibernate in the garden? The sunny, warm temperatures are delaying some plants from getting fully ready for the winter. The importance of plants getting preparing for the upcoming winter should not be underestimated. Winter is a harsh season.
Early winter ice storms won't harm this pansy flower but other plants may be damaged

Early winter ice storms won't harm this pansy flower but other plants may be damaged

Unseasonably low temperatures within the next couple of weeks will damage plants that are not fully “hardened-off” or those that are marginally hardy. This is particularly true in our area of unreliable snow cover. Gardeners cannot be guaranteed the insulating protection of snow.

Other situations that might cause havoc on plant health this winter are a quick thaw in January or February resulting in flooded areas over the frozen soil. A quest to keep roads and paths clear of snow and ice means that mountains of salt and sand are spread each winter. Heavy snow is another concern. Evergreen trees laden with snow may look picturesque but early season, waterlogged snow could bend the branches leaving them permanently misshapen. Wind scorch is an unappealing sign of the harshness of winter, but it is one of the less damaging factors. A more serious concern is the damage caused by mice gnawing on tender plant stems. This is usually not noticed until plants are struggling to grow the following season.

Early winter snows can damage plants that aren't ready for the sudden chill

Early winter snows can damage plants that aren't ready for the sudden chill

Preventing damage due to low temperatures is often beyond the control of gardeners. Fluctuations below the annual average low temperature are to be expected during most winters. Gardeners can only hope that their plants have hardened off or are protected in a microclimate and will be able to withstand an early cold spell. Plants are better able to survive if there has been a gradual decrease in temperature instead of a sudden sharp drop. To have reliably hardy plants that are not damaged by low temperatures, select plants that can grow in temperatures that are 2 hardiness zones colder than your garden’s zone. This is wise advice, but it is hard to follow. There are so many exciting marginally hardy plants that make tempting the fates of nature hard to resist. Identify microclimates in your garden where these tender plants can have a bit of protection from the winter weather. A building or evergreen hedge can create such a microclimate.

The January thaws have a positive psychological effect on humans, but are deadly for some plants. The freezing and thawing cycle caused by daytime temperatures above 0 degrees C. and freezing nighttime temperatures is hard on many perennials and some thin-bark trees. Plant tissues expand during the day and contract during the night. For thin-bark trees like the London plane tree, this causes a split in the bark on the southwest side. Often this repeated freezing and thawing prevents the split from healing until spring arrives. For perennials that grow from a crown or are newly planted, the freezing and thawing action might heave them out of the ground. This will leave them exposed to the drying effects of the sun and wind. Inspect your garden during the January thaws and gently press plants back into the soil.

A less frequent injury caused by the winter weather is flooding damage. This is often a short-term problem in late winter when the ground is still frozen and the first heavy rains arrive. Many low-lying areas can be filled with standing water for days. Healthy plants are able to withstand a limited amount of flooding. During late winter, trees are still dormant and little oxygen is exchanging through the roots. A short duration of flooding should not harm them. Willows, bald cypress and alders are more resistant to flooding damage.

Heavy layers of ice can damage just as much as wet, dense snow.

Heavy layers of ice can damage just as much as wet, dense snow.

Wet, heavy snow is a potential problem at the beginning and end of the winter. This type of snow can cause damage to evergreens or hedges. These plants that do not have strong stems to withstand the weight of snow or because of their shapes, do not shed the snow as it piles up. Boxwood that has not been trimmed is especially prone to snow-load damage. Heavy snow or ice will force the branches downward and leave gaping holes in the shrub that might be permanent. Some cedars (Thuja) and pencil point type junipers might also be damaged. Snow loads could also damage hedges that have been trimmed with a flat top. Minimize the amount of horizontal surfaces that are present on weak-stemmed hedges. Creating a slight angle on the sides is an excellent solution to this problem. To prevent snow-load damage on upright plants, support the branches with fine netting or tie up the plant like a Christmas package with garden twine. In many cases, a broom will work to remove the snow before it becomes heavy enough to weigh down the branches.

The cold, drying winter winds can damage some broad-leaf evergreens, especially Mahonia (Oregon grape). Winter weather causes browning of the outer edge on exposed leaves. In the spring the plant will send out new growth to cover this browning, but it looks bad for a time. Other conifers such as those with golden-coloured foliage and dwarf Alberta spruce might also suffer browning from drying winds and sun during the winter. Plant these in a location where they receive protection from the south and west, use an anti-desiccant spray, wrap them with burlap, or live with the temporary discolouration.

So what can be done to battle the latest weather anomaly? Pretend that the garden has been transported to England or change the calendar to April? The best action is to prepare plants wherever possible for the winter. Hill roses, mulch perennials, and line with burlap where it has been done in previous years. A little effort to give some protection will be well worth it.

Garden Plants for the Overlooked Fourth Season

Perennials in the Garden for Fall and Winter Interest

Looking for ideas on how to design an attractive garden for the overlooked winter season usually means wading through lists of trees and shrubs for the most attractive fall foliage colour and winter form.  With a little luck, there might even be a few days of colourful berries to peak interest before birds or cold temperatures change the view.  After a few minutes the  lists become quite monotonous with two key plants; winterberry holly and red twig dogwood.  When many gardeners are faced with staring out the window for what could be months at the frozen landscape, it is important to broaden our list of winter interest landscape plants.

Snowy winter scene

Snowy winter scene in upstate New York

There are many more plants that can add interest to the picture than Ilex and Cornus.  Very little attention is paid to the plants at our feet. This group of overlooked plants are the perennials. Perennials can offer very interesting effects during the fall and winter as a result of their attractive seedheads. Some perennials have strong semi-woody stems that will stay upright through the entire winter, while others will give a good display through the fall and early winter before rain, wind and snow cause them to lean with casual artistry.

The showiest feature perennials offer through the snowy winter months is attractive seedheads. Wind blowing the tall stems of Eupatorium maculatum (Joe-Pye Weed) will make them sway like a living curtain. Another reason for leaving perennials standing in the fall is to see the contrast between the dark colours of many plant stems and the light colours of falling leaves and snow. The dark, woody seedpods of Iris sibirica (Siberian Iris) are very interesting when the three sectional capsule is surrounded by yellow birch leaves that have fallen around the clump. Leaving perennial seedheads intact after their flowers have finished blooming also is a benefit to wildlife. Echinacea purpurea (Purple Coneflower) is excellent for attracting finches and sparrows to the garden that are looking for food. An additional ornamental benefit to leaving perennials unpruned once they have finished blooming is that many have attractive seedheads that can be dried for fall or winter bouquets.

The following perennials are recommended because they have attractive properties in the fall and winter.

Acanthus spinosus (Spiny Bear’s Breeches) remains attractive long after the mauve-white flowers have fallen. The seedheads have the same nodding shape of the flowers. They are held high above the foliage and remain quite attractive into the fall. The spiny foliage may even remain semi-evergreen through the winter if they are in a mild enough location (with snow cover).

Many of the Achillea (Yarrow) have attractive upright, sturdy seedheads that look effective during the beginning of the winter. Since the fall is a time that Achillea often reblooms, many flowers are smaller and stems are not as sturdy as earlier in the season. Still some cultivars are excellent for fall and winter interest. Liatris spicata (Spike Gayfeather) also has attractive seedheads. Liatris has a fluffy, brown upright spiky structure that has good holding power into the winter.

Yaupon holly after a February ice storm

Yaupon holly after a February ice storm

The best time for Alchemilla mollis (Lady’s Mantle) seed displays is just after blooming early in the summer. Heavy rains during the late summer and fall will often cause the weak seedheads to lie horizontally. This in itself can be attractive in the winter as the tan star-shaped seeds are held above the leaves. One of the potential disadvantages of leaving the seedheads on these plants is that Lady’s Mantle will self-seed extensively the following year. Coreopsis verticillata (Threadleaf Coreopsis) also has attractive seeds and will also self-seed if they are left on the plant over winter. This is a small price to pay for an attractive winter display.

The pink blooms of Anemone hybrida (Japanese Anemone) seem to be everywhere lately. So many new and improved cultivars are finding their way to the garden centres that they are finding their way to many gardens. Japanese anemones are excellent for late season blooms (almost until the frost!). Some of the early blooms may even progress into seed heads that open to reveal attractive white cottony seeds.

Angelica is an interesting plant. The most commonly grown ornamental species is Angelica gigas. If this plant is allowed to flower and set seeds it will die and act like a biennial. If the plant is allowed to flower and the seeds removed before they mature, the plant acts like a short-lived perennial. If the plant is grown as a biennial, some of the seeds may germinate and start to grow the following year. If it is left to set seed, the resulting form is a very dramatic. It resembles a tall umbrella-like structure that could reach 2 metres in height.

Some perennials will actually live through the winter better if they are not pruned in the fall. Artemisia (Silver Sage) and Filipendula (Queen of the Prairie, Meadowsweet)
are two of these plants. Do not prune these plants in the fall. Leave them through the winter and clean them up in the spring. Some of the taller blooming cultivars may “recline” during the winter but this is a small price to pay for increasing plant survivability.

 Asclepias tuberosa (Butterfly Weed) has orange blooms that progress to small milkweed-shaped seedpods late in the summer and fall. These split open in the fall to release silky topped seeds. If seed-collecting admirers can be encouraged to leave the pods, these plants are quite attractive. This might be a lost cause since so many want this plant for their garden.

Salvia left unpruned in the fall has a better chance of survival through the winter and the seedheads add winter interest.

Salvia left unpruned in the fall has a better chance of survival through the winter and the seedheads add winter interest.


Fall and asters go together like tulips and spring. One plant that is an exceptional introduction is Aster frikartii ‘Monch’ (Monch’s Frikart Aster). This is a shorter, earlier aster that has very little trouble with pests and diseases. Leaving the seedheads standing makes sense for several reasons. Chief among these reasons are for winter architectural effect, for feeding the birds and to increase its winter survivability. A white flowering aster-like plant called Boltonia asteroides ‘Snowbank’ (Bolton’s Aster) and the tall, yellow blooms of Patrinia scabiosifolia can also be treated this way.

Many astilbe including Astilbe arendsii have attractive plume-like seed structures that create an excellent vertical accent effect through the winter. These plants also fare better if the foliage and seedhead is not pruned in the fall. Chelone lyonii (Turtlehead) is also a plant that should not be pruned in the fall. Do the clean up for both of these in the spring.

The foliage and flower stems of Ceratostigma plumbaginoides (Leadwort) will provide an attractive display through the fall and winter. The main reason for leaving this plant standing is to mark its location the next spring. Ceratostigma is unusually late to emerge and often waits until it is time to plant annuals before it peeks from the soil. Having some remnants of the plant still present means that that it will not be disturbed while it is dormant.

The tall seedheads of Cimicifuga racemosa (Bugbane), star-shaped seeds of Dictamnus albus (Gasplant) and the horizontal structures of Crocosmia (Montbretia) provide attractive interest if they are left standing during the winter.

Getting Dendranthema (Chrysanthemum) and Lobelia cardinalis (Cardinal Flower) to overwinter is often a tough task under the best of conditions. Leaving the entire plant standing in the fall will help with winter survivability. Even though the plants often have a sprawling way of growing, this does add interest when the snow flies. Letting cardinal flower self-seed increases the chance that some plants may overwinter (even if it is as seed).

Two architectural plants that add dramatic interest during the summer, fall and winter are Echinops ritro (Globe Thistle) and Eryngium planum (Flat Sea Holly). Both of these plants are known to self-seed if the seedheads are left on the plant. If self-seeding is not a problem in the garden leave these plants alone until the spring so that the round and spiny structures can be fully appreciated.

One of the unsung treasures of the perennial border are the Gaura lindheimeri cultivars (Butterfly Gaura). These plants have months of light airy dancing blooms and once the frost comes; they have attractive red tints on the flower stems in the late fall. These turn brown during the winter.

Getting Papaver orientale (Oriental Poppy) to have seed pods for winter interest is a battle. Most often the seed pods are harvested in the summer and fall for floral arrangements instead of leaving them on the plant. With such an attractive seed pod who can blame the early harvesters?

January view at the Ladybird Johnson Wildflower Center, Austin, TX

January view at the Ladybird Johnson Wildflower Center, Austin, TX

Silvery stems and seedheads are the reward during the winter for leaving Perovskia atriplicifolia (Russian Sage) standing until the spring. Since this plant likes to grow with a mass of divergent stems, the effect is quite interesting. Prune Russian sage to 15 cm (or lower) in the spring if killed to the ground by cold weather.

Both the excessively tall Rudbeckia nitida ‘Herbstsonne’ (Black-eyed Susan) and the shorter coneflower perennial staple called Rudbeckia fulgida ‘Goldsturm’ might fall over during the worst winter weather. Nonetheless the “coneflowers” are excellent winter interest plants because of their seed structures and the birds love to feast on the seeds.

One of the best winter interest perennials are the Hylotelephium ‘Herbstfreude’ AKA Sedum ‘Autumn Joy’. The brown spent flowers hold up very well to rain, snow and ice (and look great during all of these conditions). Often the seedheads look so good that they are used in early spring flower arrangements. Don’t touch them at all in the fall.

Several other perennials are attractive during the winter because of their evergreen foliage. These are Ajuga reptans cv. (Carpet bugleweed), Helleborus orientalis (Lenten Rose), Heuchera sanguinea (Coralbells), Lavandula angustifolia (English Lavender), Teucrium chamaedrys (Germander), and Thymus serpyllum (Mother-of-Thyme).

Garden Trivia Quiz

Fun with Useless Garden Trivia Stuff?!??

Do you know the difference between Corylus and Corylopsis? Well you don’t have to know the answer for this fun gardening trivia quiz. Gardeners or garden lovers eager for some fun investigation and a chance to test their knowledge of vegetables, perennials, trees, annuals, pests, weeds and indoor plants are invited to tackle the following quiz. (The answers are in the next post.)

1. That warm feeling from hot peppers is measured in units that honour the man who discovered the complicated way to measure the heat of peppers. What are the units that measure pepper heat?

2. Zucchetta Rampicante is an heirloom vegetable vine from Italy. What type of vegetable is it?

3. Some tomatoes are true vines that don’t stop growing until the frost. Are they determinate or indeterminate plants?

4. This vegetable has many personalities. When it is growing in the herb garden it is often called Chinese parsley. When the seeds are gathered for mildly spicy casseroles and baked goods it is called coriander. Used fresh or dried in India it is called dhania. What is it called when the leaves are harvested for salsas and salads?

5. The flowers, stems, leaves and seeds of foxgloves are very attractive but deadly. What makes this popular perennial so harmful?

6. Whirling butterflies is the cultivar name of a perennial with dancing blooms on long wiry stems. The flowers open whitish pink and turn rosy pink as they age. What is the plant?

Purple Coneflower and Golden Hakone grass Purple Coneflower and Golden Hakone grass

7. Some perennials have a colour identity problem. Purple coneflower is not really purple it is pink. ‘Husker Red’ is a foxglove penstemon that in real life has maroon tipped leaves and soft lavender flowers with white throats. What is the flower colour of a vigorous groundcover called Lamium ‘Beacon Silver’?

8. Why is Physostegia called the obedient plant when it spreads so disobediently?

9. Ligularias have big, bold leaves that often look like wilted lettuce in the garden. Where would this plant be happier?

10. Black walnut trees exude a toxic material from their roots to exclude other broad-leaved plants (including their own seedlings) from growing nearby and providing competition. What is the toxic substance?

11. The oil from the roots of a tree native to most of the eastern part of the United States and Southern Ontario was originally used to flavour root beer. What is this tree with mitten shaped leaves?

12. This massive native tree has a botanical name that is derived from the Greek word “leirion” meaning lily and dendron meaning “tree”. Native peoples used the tall straight trunks of this tree for large canoes carrying 20 people or more. The attractive yellow and orange flowers bloom in late May and early June. What is this tree?

13. What tree is the official tree of Maine and Ontario, Canada?

14. Aucuparia is part of a botanical name for a small tree or tall shrub meaning “I catch birds”. What is this plant?

15. This ornamental plant in the annual garden still produces a few tubers like its close relatives found in the grocery story vegetable section. What is it?

16. Deadheading is a term for a frequent practice done by anyone growing marigolds, geraniums and zinnias. What is happening to these plants?

Name this Canna? Can you name this Canna?

17. One of the most popular cannas for dramatic effect has bronzy purple and yellow striped leaves and orange blooms. What is the name of this canna?

18. This annual is called false Queen Anne’s Lace or Bishop flower for its cluster of lacy white blooms. How tall does it grow?

19. Zinnia flowers come in a rainbow of colours. What unusual colour is the one called ‘Envy’?

20. Where in the world is annual lobelia (Lobelia erinus) native?

Garden Challenges
21. Which voracious green caterpillar can reach 4 inches (10 cm) in length while devouring the vegetable garden?

22. These dime size black spots form on the upper surface of maple leaves during the second half of the summer. What is this called?

23. Which four houseplant and tropical-attacking insects excrete a substance called honeydew?

24. Cutting both ends out of a metal soup can and pushing it 2 inches (5 cm) into the lawn is a good way to tell if an underground insect is present. Which serious lawn pest potentially floats to the top a few minutes after water is added to the can?

25. A white dusty coating on a lilac leaf is a fungus disease. What is it?

26. This vine, shrub or groundcover plant has three leaflets, white berries and small greenish-white blooms. Most people regret coming into contact with the plant’s sap. What is the plant?

27. The stems on this weed are triangular. It loves to grow in moist, sandy fields or gardens throughout most of the warm and temperate zones of the world. What is it?

28. This weed looks like a scouring brush because it has no leaves, flowers or seeds. It reproduces by spores and spreads by underground stems. The stems can easily be pulled apart at the nodes and put back together like interconnecting pipe. What is the name of this plant?

29. Ragweed has inconspicuous male flowers that produce huge quantities of light pollen that can fly in the wind for more than 125 miles (200 km). This plant is the most important cause of hay fever allergy suffering during which two months?

30. Poison hemlock, goutweed, Queen Anne’s lace, and water parsnip all belong to the same family of plants. What is this family called?

Indoor and Tender Plants
31. What is the botanical name for weeping fig?

32. Frangipani is a large tropical plant known for its colourful blooms and outstanding _________.

33. Bromeliads belong to the same family as this popular tropical fruit. What is the famous bromeliad family member?

34. The looking glass tree is named for its silvery mirror-like foliage that reflects the sun. What is this tropical tree?

35. Kiss-me-quick or yesterday-today-and-tomorrow is the name of a tropical shrub that has flowers that are pale violet when they first open. After a day the fragrant flowers change colour to white. Which plant is this?

Garden Trivia Quiz Answers

Garden Trivia Answers are Revealed

The suspense is over for all fun-loving gardening trivia buffs. Here are the answers to the trivia quiz and in some cases an explanation.



1. That warm feeling from hot peppers is measured in units that honour the man who discovered the complicated way to measure the heat of peppers. Pepper heat is measured in Scoville Units in honour of Wilbur Scoville who invented the scale in 1912.

2. Zucchetta Rampicante is an heirloom vegetable vine from Italy. It is a summer squash or zucchini.

3. Some tomatoes are true vines that don’t stop growing until the frost. These are indeterminate because they don’t stop growing once they start flowering.

4. This vegetable has many personalities. When it is growing in the herb garden it is often called Chinese parsley. When the seeds are gathered for mildly spicy casseroles and baked goods it is called coriander. Used fresh or dried in India it is called dhania. It is called cilantro when the leaves are harvested for salsas and salads.

5. The flowers, stems, leaves and seeds of foxgloves are very attractive but deadly. The chemicals deslanoside, digitoxin, digoxin, and digitalis glycosides make this popular perennial so harmful.

6. Whirling butterflies is the cultivar name of a perennial with dancing blooms on long wiry stems. The flowers open whitish pink and turn rosy pink as they age. The plant is called Gaura lindheimeri.

7. Some perennials have a colour identity problem. Purple coneflower is not really purple it is pink. ‘Husker Red’ is a foxglove penstemon that in real life has maroon tipped leaves and soft lavender flowers with white throats. A vigorous groundcover called Lamium ‘Beacon Silver’ has pink blooms and silver foliage edged in green.

8. Physostegia is called the obedient plant, not because it stays contained but because the flowers move on a hinge and stay in place.

9. Ligularias have big, bold leaves that often look like wilted lettuce in the garden. The plant would be happiest in a cool and moist location.

10. Black walnut trees exude a toxic material from their roots to exclude other broad-leaved plants (including their own seedlings) from growing nearby and providing competition. They exude a toxic substance called Juglone.

11. The oil from the roots of a tree native from Maine to New York and Michigan and south to East Texas and central Florida was originally used to flavour root beer. This tree with mitten shaped leaves is called Sassafras.

12. This massive native tree has a botanical name that is derived from the Greek word “leirion” meaning lily and dendron meaning “tree”. Native peoples used the tall straight trunks of this tree for large canoes carrying 20 people or more. The attractive yellow and orange flowers are blooming now. The tree is Liriodendron or tulip tree (yellow poplar or tulip poplar).

13. Maine and Ontario’s official tree is the Eastern White Pine (Pinus strobes).

14. Aucuparia is part of a botanical name for a small tree or tall shrub meaning “I catch birds”. The plant is a mountain ash that has fruit that are used to catch birds in Europe.

15. This ornamental plant in the annual garden still produces a few tubers like its close relatives found in the grocery story vegetable section. The ornamental vegetable is sweet potato vine (Ipomaea batatus).

16. Deadheading is a term for a frequent practice done by anyone growing marigolds, geraniums and zinnias. The term refers to the act of removing the spent flowers.

17. One of the most popular cannas for dramatic effect has burgundy purple leaves with red and yellow striped leaves and orange blooms. This canna is called  Tropicanna, ‘Orange Durban’ or ‘Phaison’.

18. This annual is called false Queen Anne’s Lace or Bishop flower for its cluster of lacy white blooms. It is Ammi majus and it will grow to 75 cm (30 inches).

19. Zinnia flowers come in a rainbow of colours. What unusual colour is the one called ‘Envy’? ‘Envy’ is a delicate shade of green.

20. The annual lobelia (Lobelia erinus) is native to South Africa (Cape of Good Hope area).

Garden Challenges
21. A voracious green caterpillar can reach 4 inches (10 cm) in length while devouring many items in the vegetable garden. This is the tomato hornworm, which is a sight to see and hear chewing.

22. These dime size black spots form on the upper surface of maple leaves during the second half of the summer. This unattractive yet relatively harmless disease is called tar spot.

23. There are four houseplant-attaching insects that excrete a substance called honeydew. These are aphids, scale, mealybug and whitefly.

24. Cutting both ends out of a metal soup can and pushing it 2 inches (5 cm) into the lawn is a good way to tell if an underground insect is present. Chinch bug is the serious lawn pest potentially floats to the top a few minutes after water is added to the can.

25. A white dusty coating on a lilac leaf is a fungus disease called powdery mildew.

26. This vine, shrub or groundcover plant has three leaflets, white berries and small greenish-white blooms. Most people regret coming into contact with the plant’s sap because it causes itchy blisters. It is called poison ivy.

27. The stems on this weed are triangular. It loves to grow in moist, sandy fields or gardens. It is the troublesome weed called yellow nutsedge.

28. This weed looks like a scouring brush because it has no leaves, flowers or seeds. It reproduces by spores and spreads by underground stems. The stems can easily be pulled apart at the nodes and put back together like interconnecting pipe. It is called horsetail and is quite persistent.

29. Ragweed has inconspicuous male flowers that produce huge quantities of light pollen that can fly in the wind for more than 125 miles (200 km). This plant is the most important cause of hay fever allergy suffering during August and September for many people.


30. Poison hemlock, goutweed, Queen Anne’s lace, and water parsnip all belong to the same family of plants. These plants are in the carrot or parsley family (Apiaceae or Umbelliferae)



Indoor and Tender Plants
31. What is the botanical name for weeping fig? Ficus benjamina.

32. Frangipani is a large tropical plant known for its colourful blooms and outstanding fragrance.

33. Bromeliads belong to the same family as this popular tropical fruit. The most famous member of this family is the pineapple.

34. The looking glass tree is named for its silvery mirror-like foliage that reflects the sun. The tree is called Heritiera.

35. Kiss-me-quick or yesterday-today-and-tomorrow is the name of a tropical shrub that has flowers that are pale violet when they first open. After a day the fragrant flowers change colour to white. The shrub is called Brunfelsia.

Fabulous Fruits for the Fall

Fruitful Fruits of the Fall

The end of the growing season is the time to enjoy the fruits of the garden. Unveiled by the falling curtains of leaves are many shrubs and trees that brighten the landscape with vivid fruit. Some of the fruit stays for a lengthy time (like sumach) but many others attract feathered admirers and could vanish in an instant once they are discovered. This is the best time to appreciate the showy features of some overlooked (and underused) plants in our landscape. This summer has been quite good for the production of fruit on many plants.

One shrub to admire is the Firethorn (Pyracantha coccinea). Firethorn produces heavy clusters of orange-red fruit that have the brilliance of fire. The fruit, which has beacon-like properties, can be seen for a great distance because of the contrasting dark green foliage. This shrub is sometimes trained as an espalier form against a wall or fence.

Porcelain berry (Ampelopsis brevipedunculata) is a surprise attraction in the fall garden. This relative of the grape vine does not justify its existence all summer. It has a lacklustre leaf and borders on being too rampant. Finally after a lot of patience from the gardener, it starts to redeem itself in October. The small, green pea-shaped fruit starts to ripen and turn a light blue colour. It then turns darker blue and finally it changes to a purple colour. This transition happens at differing speeds so that all colours are present on the vine at once. The beauty of this vine is this remarkable array of colours. Unfortunately, the foliage (until it falls) hides some of the fruit. The first week of November is usually the best time to see the display of lilac to amethyst-blue coloured fruit when it is most showy just after the foliage has fallen.

Virginia creeper is a durable, reliable vine that is often dismissed as a garden plant because it is viewed as being old-fashioned. The vine botanically is called Parthenocissus quinquefolia and has dark blue berries that hang down in miniature grape-like clusters. This fruit is also most effective after the leaves have fallen. The fruit stays on the vine through the winter and appeals to many birds as a secondary source of food.

Euonymus are not one of the shrubs that would normally be considered for a list of fruiting plants. Some cultivars of Euonymus fortunei have an adult form that matures to produce flowers and fruit. The fruit is a creamy-white capsule that opens to reveal several round seeds that have an attractive orange-red coating. The fruit is a late winter meal for birds. The cultivar ‘Vegetus’ has large, green, rounded leaves and is quite reliable about producing bright orange seeded fruits.

The rich, red seedheads of the Staghorn sumac (Rhus typhina) bring back memories to many people of fall hikes through local parks. The fall glory of this large native shrub is from the berries that also delight some 93 species of birds. The colourful fruit can be seen (if the birds don’t eat it) from October until the new flowers appear in May.

Cotoneasters are a valuable groundcover shrub that have become slightly overused in larger landscaping sites. Some of the smaller types are ideal for home gardens and have attractive fruit during the fall and early winter months. One of the best (and most popular) is the rockspray cotoneaster (Cotoneaster dammeri ‘Coral Beauty’). This variety will reliably produce a heavy crop of fruit. The leaves are a glossy, dark green colour which is a nice complement to the fruit. Another valuable groundcover plant is Cotoneaster horizontalis. It has low, horizontal branches that are great for growing over a wall or down a slope. In the fall it is decorated with small, round, scarlet fruit.

The shrub called winterberry (Ilex verticillata) is a true holly that has deciduous leaves. The yellow-bronze foliage falls in early November revealing small red fruit clustered along the stems. The showy fruit gleam like red Christmas lights. This interesting plant is native to an area from Nova Scotia to western Ontario and is hardy from zones 4-9. Each plant is either male or female and both must be nearby to produce fruit. The best growth occurs in a location that has moist, acidic soils although it is growing well in alkaline soils at the Niagara Parks Botanical Gardens. This shrub is valuable in the landscape because it is somewhat shade tolerant. More than twenty-two types of birds will feed on the fruit and eventually strip it clean in early winter.

One shrub that has fruit that the birds do not touch is the European Cranberrybush (Viburnum opulus). The vivid, red, berries are bitter and distasteful to birds and humans. The fruit persist into the winter and eventually look like dried, shrivelled, red raisins.

As an alternative, the native shrub called High bush cranberry or American Cranberrybush (Viburnum trilobum) has similar clusters of bright red fruit that is prized by thirty four species of birds. This tall shrub is hardy to zone 2 and has fruit that can be harvested for making preserves or jellies.

Crabapples are a natural to include on a list of plants with notable fruit. Of all the numerous cultivars of crabapples, Malus ‘Red Jade’ is one of the best small trees for showy flowers and attractive fruits. It has small, bright, cherry-red fruits that last well into winter. They resemble a crop of maraschino cherries hanging on the tree branches. The weight of the fruit makes the naturally pendulous branches weep even further. It is a beautiful sight.

The white fruits of snowberry (Symphoricarpos albus) hang on the barren stems in early winter. The small shrub is most effective when it is planted against a backdrop setting of evergreens. Once again, the fruit show best in early winter just after the leaves have fallen.

The mountain ash (Sorbus aucuparia) has brilliantly coloured fruit in the fall but rarely has it into the winter. Invariably, word spreads that the fruit is present and a flock of cedar waxwings will strip every fruit from the tree in an instant. There are new cultivars appearing in the nursery that have white, yellow, orange, or coral coloured fruits.

Beautyberry, as the name suggests, is a plant with outstanding fruit. Botanically it is Callicarpa bodinieri var. giraldii. This shrub is originally from China and came into cultivation in western gardens at the turn of the century. The fruit on this shrub are a rich lilac-purple colour. The fruit are produced in small, delicate clusters close to the stems. The best time to appreciate the beauty of the fruit is just after the foliage has fallen in early November.

Whatever the fruiting plant, design your garden so that the fruit (and feasting birds) can be seen and appreciated from your house window. Many plants are particularly attractive if they have a dark green backdrop of evergreens to accentuate their brilliant display of fruit.

Efficient Perennial Maintenance

Plan First to Efficiently Maintain Perennials

The following are a few tips on developing a strategy plan to maintain your perennial plants more efficiently.

Graceful drifts of perennials greet visitors at the entrance garden to the Niagara Parks Botanical Garden and School of Horticulture in Niagara Falls, Ontario Canada.

Graceful drifts of perennials greet visitors at the entrance garden to the Niagara Parks Botanical Garden and School of Horticulture in Niagara Falls, Ontario Canada.

• Draw a sketch or plan of each perennial bed or border. Indicate each plant on a scaled drawing. The time that it takes to create this valuable plan will be well spent when garden revisions are being done. Use this plan to record your ideas while they are still fresh.
• Take pictures of the garden during each season. Although this is often the lowest priority item on your “to do” list, pictures are essential to help recreate the ideas noted on your plan. This is particularly helpful if you are redesigning your perennial garden in the winter.
• Keep records of each plant’s characteristics. Draft a chart of their height, width, flower colour, blooming time, and blooming duration. Include a final column on the chart where notes can be added about other attributes.
• Before a maintenance plan can be created for the garden, some research is necessary. Add several maintenance categories to your plant charts. Include propagation records (division, layering, cuttings, seeded), staking, deadheading, pest and disease problems.
• Be observant in the garden. Take note of any plants that are showing signs of unhealthy growth and try to find out why.
• If you wish to lower the amount of maintenance required for your perennials, try using perennial groundcovers such as Ajuga, Alchemilla, Aubrieta, and Geraniums. These cover an area with their thick leaves and keep out weeds. Also to lower maintenance -don’t fuss with your plants. If a clump of candytuft needs deadheading- use hedge shears to get the job done faster.
• Plant in groups or masses of odd numbers. Groups of plants will be better suited to keep out the weeds and will be faster to maintain. Many smaller groups of diverse plants will require more time to maintain.
• Consider the timing of your activities. By deadheading (removing the finished flowers) candytuft before the seeds are dispersed, the plant does not selfseeding. A weeding job has just been eliminated.
• Accomplish as many tasks as your time and the plants will allow. Think of what will need to be done to maintain your perennials before your can return to the garden and do it now. Think about anticipating “must do” tasks that are on the horizon. Staking a plant before it needs staking is much easier than doing it after it has blown over.
• No time to spend time? Don’t use plants that need lots of TLC in your garden. These are the finicky plants that have to have special soil, precision watering, constant grooming and copious pest control to look good. If you are short on time to maintain perennials do not use these plants.

Here’s a list of tough, durable, easy care perennials for a sunny location:
• Achillea millefolium (Yarrow), zone 4-8
• Campanula carpatica (Carpathian Bellflower), zone 3-8
• Cerastium tomentosum (Snow in Summer), zone 3-8
• Coreopsis grandiflora (Tickseed), zone zone 3-10
• Echinops ritro (Globe Thistle), zone 3-8
• Echinacea purpurea (Purple Coneflower), zone 3-10
• Gaillardia grandiflora (Blanketflower), zone 3-10
• Phlox subulata (Creeping Phlox), zone 3-9
• Rudbeckia fulgida (Showy Coneflower), zone 3-9
• Sedum and Sempervivum species (Stonecrop and Hens & Chickens), zone 3-10

Schedule your perennial maintenance activities and prioritize your work. Group your perennial garden activities into three categories.
1) Things that must be done in the perennial garden so that plant will survive. These include watering, weeding, and pest control.
2) Things that should be done in the perennial garden but are not absolutely critical to the plants health. These are fertilizing, mulching, and fall clean up.
3) Things that might be done in the perennial garden but are definitely not critical to the plants health. These include deadheading, shearing, pinching, cutting back, staking, thinning, dividing, moving, and winter protection.

How much time do you want to spend on each of these categories? Will this change with the time of year? Throughout the season keep track of the activities that fit into each category. Evaluate these categories at the end of one season. Do you need to change your priorities?

Debunking Garden Myths

Garden Myths Not Worth Repeating

Myths, old wives tales, and folklores abound even in the world of gardening. Gardening lore often gets passed from neighbour to neighbour as homegrown tips based on little or no scientific research. The myths start out as common sense conclusions and keep getting perpetuated time after time. Pretty soon they are part of the global gardening consciousness and they are believed to be true. Once this happens it is almost impossible to undo the belief. The poinsettia poison myth is still being trounced after eighty years. Well, here’s my attempt to dispel some popular garden myths.

Myth: Botanical “natural” pesticides are toxic to pests and harmless to other living things (including gardeners). Not true, in fact some botanical pesticides that are derived from poisonous plants are even more toxic than commercially prepared ones. Both pyrethrum (made from Chrysanthemum cinerariaefolium) and rotenone (made from two tropical legume family plants, the South American Lacepod or Lonchocarpus and the Asia’s jewel vine or flame tree which is known botanically as Derris) are popular botanical pesticides. Pyrethrum and rotenone are moderately toxic to humans (particularly children) when inhaled or ingested. Interestingly both are extremely toxic to aquatic life, and are used as fish poisons.

The flowers of the chrysanthemum used to make pyrethrum are harvested shortly after they open and are either dried and pulverized or the oils from the flower are extracted using solvents. The active ingredient works on the nervous system to cause paralysis and death (if in sufficient quantities). Cats are particularly susceptible to poisoning from pyrethrums.

Rotenone is a contact and stomach poison that is made by grinding up roots and varies in its human toxicity from very high to low depending on how much of the pure derris root is used in the pesticide. Treat natural pesticides with the same caution that synthetic ones deserve (or give them even more). One of the most toxic pesticides is nicotine, which is derived from the tobacco plant.

Myth: The soil under oaks, cedars and pines is acidic. The top inch or so might be acidic, but if the bedrock underneath is limestone then the soil above that rock will be on the alkaline side. Oak leaves, cedar leaflets and pine needles have to build up for centuries to make a significant amount that will have any impact on alkaline soil.

Myth: Moss grows in lawns that need lime. Lots of conditions favour the growth of moss in lawns. Having an acid soil is not the most significant one of them. The most important reason that moss is found in the lawn is that conditions are not favourable for a lush, healthy lawn. Moss is an opportunity seeking plant and will settle almost anyplace that there’s an open spot. Too much shade, poor drainage (moist conditions), poor fertility or compacted soils are all conditions where lawns do not grow well. When this happens moss is almost certain to arrive. Don’t add lime to correct a moss problem unless a soil analysis indicates an excessively acidic result.

Myth: Mushrooms and toadstools sprouting in the lawn mean that the soil is deficient. On the contrary, fungi such as mushrooms and toadstools are living off nourishing decaying material. A rotting tree root or other decaying organic matter is likely the cause of the fungi. This is a good sign that there’s nourishment being added to the soil. The visible structures are the flowering and fruiting portion of an extensive underground plant.

Myth: Ants are needed to make peony flowers open. Many people believe that ants are actually eating the waxy coating from the peony so that the flower can open. Others believe that the peony is secreting a sugary substance that attracts ants to feed. In any case, the ant is enjoying a symbiotic relationship with the peony and is not doing any harm by being on the flower bud. Once the bloom starts to open the ants vanish. Peony flowers can open just fine without any ants – just ask a florist.

Myth: Poinsettias are poisonous. This hugely popular garden myth is not true. There have been no cases of plant poisoning from poinsettias. This poison myth started in 1919 when a two-year-old child of an army officer stationed in Hawaii died of poisoning. The cause was incorrectly attributed to a poinsettia leaf. To persuade the public of this myth, members of the Society of American Florists frequently eat poinsettias for the press in December. The leaves taste like a bitter radicchio and won’t kill you, just make you sick. The plant though should not be eaten and is hazardous because of the milky sap. The sap can cause an allergic reaction for some people.

Myth: Some plants can repel mosquitoes. Amazing but not true, there are no plants that repel mosquitoes. If you rub the leaves of certain plants onto your skin, the oils and aromas can help discourage mosquitoes from biting. It is asking a lot of a plant to release essential oils into the air in quantities that can keep mosquitoes away for distances like 6 feet though.

Myth: Clay pots are better for houseplants than plastic pots. Clay pots cause the moisture in the soil to evaporate faster than plastic pots. This can be helpful for houseplants if the waterer is heavy handed – then clay is better. If houseplants are watered only when they need water instead of on a regular schedule then plastic pots should be adequate.

Myth: It doesn’t pay to use leftover seeds from flowers and vegetables. Most open packets of seed start to loose their viability as soon as they are exposed to heat and extreme humidity levels. If seeds are stored under ideal conditions in a tightly sealed jar in a dark, cool, dry location then they should store well for several years. The length of time varies according to the seed. To extend the viability even further, place some powdered milk in the bottom of the glass jar to soak up humidity.

Myth: Hostas are shade plants and don’t tolerate the sun. There are many hostas that perform very well in the sun if they are given adequate moisture. In fact, the native habitat for many hostas is in a sunny location at the edge of the woods. Some hostas that tolerate more sun are: Francee, Patriot, Sum and Substance, Gold Standard and Royal Standard.

Taking a moment to look at these myths with a bit of scepticism will hopefully lead gardeners, after some critical thinking, to come to the conclusion that not all gardening lore is valid.

Looking For a Mate – Some Plants Just Change Their Sex

Some Plants Just Face Big, Big Challenges When Looking for Romance!

The plant world has some amazing ways to make sure that progeny are successfully reproduced. One of the most interesting ways of overcoming the challenge of not having the right mate nearby is solved when some plants change their sexual orientation as the need arises. This small group of plants have a very liberating “keep all options open” way of propagating themselves. Still others overcome the big challenges of finding a suitable plant mate by excreting toxic substances to keep their unwanted suitors away. Finding the right mate can be downright challenging for some among the plant kingdom.

The most novel solution to the elusive mate syndrome has been solved by plants like the saltbush.  If the opposite sex is not nearby, they just simply change sexes and continue with their propagation process. The sexually labile, Four-Wing Saltbush (Atriplex canescens) is a perennial that can amazingly change from one sex to the other at will. This plant, native to western Texas, stands a little over three feet (one metre) tall and has attractive winged fruits. Historically, the seeds were ground and used by Native Americans as baking powder when making bread.

Hollies like this Yaupon need both a male and female plant in close proximity to produce fruit.

Hollies like this Yaupon need both a male and female plant in close proximity to produce fruit.

When cold temperatures or drought make it tough for the saltbush to find the right mate — they use their ability to change sexes. Usually this change is from female to the male sexual orientation. This unusual “switcheroo” greatly increases the odds of reproducing the species by putting more male pollen into the air. The more pollen that is spread to the wind, the better the chances of producing seed. Spreading copious amounts of pollen in the wind may be romantic for plants, but it is often very unromantic for humans. An outdoor stroll for an allergy-prone person while sneezing and peering through watery eyes is not the scene that romance novels portray. When too much wind-borne pollen is in the air blame the over-exuberant male plants.

Another group of plants have to deal with the challenges of being designated male or female in a world that makes it far easier to reproduce by having both sexes in each flower. These unusual “one sex” plants are faced with the same “finding the right partner” challenges inherent in the human world. Called dioecious plants, they must have a member of the opposite sex nearby to produce viable fruit. Imagine being a dioecious plant and not being about to move in order to look for a partner of the opposite sex.

Literally the Greek word “dioecious” means “two in separate houses.”  Dioecious hollies (Ilex) are grown for their attractive fruit and should be planted in proportions of more females to males for the best show. If space is an issue in the garden, fewer males than females are needed to provide good pollination. The ratio is usually about one male for every eight female holly shrubs planted nearby. Nursery growers have made the task of determining sexes of hollies easier by giving some of their cultivars male and female gender based names – such as China Girl (I. ‘Mesog’) and China Boy (I. ‘Mesdob’) or Blue Prince (I. x meserveae cv.) and Blue Princess (I. x meserveae ‘Conapri’).

Success! Osage Orange Fruit

Success! Osage Orange Fruit

Osage orange is another plant that is dioecious and has male and female flowers on separate trees. The female trees have small green flowers that open in June, just after the leaves unfold. The male flowers are on terminal leaf spurs of the previous season’s growth and are 1 inch (2.5 centimetres) long in a raceme shape. Their pollen is light and travels with the wind. If a female tree is not within pollen range, they will not produce viable fruit. Female trees may look like they are producing their cannonball-like fruit well, but there may not be many viable seeds inside.

Other plants that have separate male and female plants are the tree of heaven, sago palm, persimmon, and many poplars. Even some herbaceous plants have this unusual arrangement. Spinach and asparagus have male and female flowers on separate plants, but they are both equally edible. For this reason they are grown from seed and no attention is made to their gender unless gardeners want to do some propagation at home and save their own non-hybrid seed.

Dioecious plants have even played a part in ancient Arabic wars. The date palm, a valuable agricultural crop in Arab countries has both male and female plants. Long ago fighting tribes would sneak into an enemy’s grove and destroy all the male trees. Without male pollen for fertilization no crop would be produced. This method of destruction, removing the less numerous male trees, was far less work than damaging the numerous female date palm trees.

Ginkgo Leaves

Ginkgo Leaves

The separation of plant sexes does have some advantages for gardeners, though. One of the slower plants to reach maturity, the ginkgo or maidenhair tree takes more than twenty years before it flowers. Since this tree is believed to be from the dinosaur era which dates back 270 million years, waiting for it to bloom so the sex can be determined is not that long in planet Earth time, but very long in a gardener’s time (about 20 years). The sex of a ginkgo tree is important to know because female trees have plum-like fruit that turn yellow when they are ripe. It’s the ripe flesh on the outside of the seed that is undesirable to many people because it contains butanoic acid and smells like vomit or rancid butter. There’s nothing romantic about a ripe ginkgo fruit smell. For plants that have objectionable smelling fruit like the ginkgo, growing only males means that human olfactory senses are not under assault when the female produces fruit. The one big disadvantage for the ginkgo is that it is almost impossible to tell the difference between male and female plants until they bloom – and then only under a microscope. Therefore gardeners must trust nursery labels, purchase a male clone variety or plant several of each sex in order to ensure that they have good odds that one of each is present.

The love for a ginkgo tree comes from its other features. Running a finger over the ridges of the fan-shaped leaf, looking at the divergent branching outline against sky, putting a leaf in a book to press (or finding one in an old book), or walking through the brilliant yellow fallen leaves can all conjure up sentimental feelings for this ancient tree. Who needs red roses and chocolates to feel romance and love? All it takes is a ginkgo tree (and a ginkgo may sometimes last a lot longer too).


Camouflaged and deadly offensive ginkgo fruit among the recently fallen ginkgo leaves.

Camouflaged and deadly offensive ginkgo fruit among the recently fallen ginkgo leaves.

Another obstacle to plant propagation occurs in the fruit tree world. Often more than one variety of a fruit tree is needed to really produce good fruit. This happens not because they are dioecious but because they are self-unfruitful. Many apples, pears and plums require pollen from another variety to have adequate pollination and good fruiting. Since these fruit trees produce pollen that is transported by winged insects other problems also come into play. The weather must be nice enough for bees to forage and the corresponding pollinating varieties must also be in bloom at the same time. To help overcome these problems, some nurseries are producing dwarf apple trees that have several varieties grafted on one plant. Now bees need only travel a few feet to perform their cross-pollination. This also solves the need to buy multiple plants if garden space is limited.

Some plants solve their reproduction challenges by chasing other plants away. Label this group of plants “anti-social” and think of them as being destined to have a solitary life without the company of others. Most of these plants are in the walnut family. This group poisons the soil around themselves so other plants stay away. Walnuts secrete a substance called juglone from their roots, decomposing leaves, and from the husks that surround their fruit. The secretion is toxic to the majority of the temperate plant world. When mature, their far-reaching roots create a neighbor-free zone that could double or triple the canopy area of the walnut. This is not a tree that is friendly to others. Luckily the fruit that it produces is highly prized by small, mobile animals that will transport it to remote locations and new communities.

Ginkgo images originally published by Wikipedia at and used under the Creative Commons Attribution/Share-Alike license.
Osage Orange image originally published by Wikipedia at and used under the Creative Commons Attribution/Share-Alike license.

Perennials for Attracting Wildlife

Selecting the Right Perennials can Easily Attract Butterflies, Hummingbirds and other Wildlife to the Garden.

Bringing birds, hummingbirds, and butterflies to the garden is a natural reward for creating a well-designed landscape. A garden that attracts and helps sustain wildlife is one that has benefits beyond just being a visually pretty display.

Female Black-chinned Hummingbird

Female Black-chinned Hummingbird

Planning a garden to attract hummingbirds, butterflies, birds, or other wildlife need not have to be done on a large scale or involve exotic plants. A wildlife garden can even be created from any existing perennial garden. Extensive garden renovation need not be necessary to make a garden into a wildlife-friendly one. Chances are good that some existing plants already attract wildlife (in a good way) and the addition of some more key attracting plants will strengthen this. Once a garden is created for a specific type of wildlife other visitors may soon follow. For example, a butterfly garden will soon attract other nectar-feeding visitors such as hummingbirds, bees, and moths.

There are a few requirements that must be met for wildlife to be comfortable in a garden before they will call it home. Wildlife must have a plentiful supply of food available during their stay. Without food to keep them well fed, they will wander looking for nourishment. Another essential is to have a supply of shallow, clean water to drink located in a protected, yet sunny spot. Finally, the garden should have shelter from weather elements and predators. Once these requirements are met, the garden will attract new residents.

Swallowtail and Tithonia

Swallowtail and Tithonia

For butterflies and moths, it is very important to select a site that is sunny and also sheltered from strong, harsh winds. Butterflies find it very difficult to fly upwind if the wind is forceful or gusty. Sun and its warming rays are important for butterfly movement during cool mornings. To give them a hand, create sheltered spots for butterflies to bask in the sun and warm their flight muscles. A mud puddle nearby will provide adult male butterflies with essential salts and minerals that they need for reproduction. Two types of food are needed for the different life stages of butterflies and moths. Nectar is needed for the adult flying stage and leafy foliage for the crawling larval (caterpillar) to eat. This combination of larval food and nectar food must be available throughout the summer and into the early fall in ample supply. Larval food requirements may be very specific for some caterpillars such as milkweeds and their relatives (Asclepias tuberosa) for monarch caterpillars.

Many people are hesitant to include larval food (called host plants) in their garden because they fear that these will become an eyesore as caterpillars devour the plants. If ample supplies of host plants are available, the damage will be widely spread and may even be very minimal in any one area. Many butterfly larvae eat very specific host plants and will stay contained on plant.

Butterflies often will seek out their favourite flowers because they are attracted to bright (purple, orange, yellow, pink, purple, or red) colours. Place these types of flowers where these fluttering garden visitors can view them. White flowers often emit a fragrance during the night that will often attract moths. Place these near a path or window so that the visitors can be admired.

The shape of a flower also will determine the type of wildlife that might be attracted to it. Flower shapes that attract hummingbirds are often not suitable for butterflies and moths. Flowers that have deep throats, are drooping, or are enclosed are not suitable for butterflies because they cannot land to feed. Their ideal flower is horizontal with a ring of petals around the perimeter for butterflies to sit and rest while feeding. Sweet, pungent, and acrid-smelling flowers also attract butterflies. Only use pesticides when absolutely necessary and all other integrated pest management strategies have been exhausted. Most pesticides are harmful to butterflies.

Butterfly Bush

Butterfly Bush

The following perennials, unless noted, are adult nectar producing plants that attract butterflies. The name in brackets is the common name. Achillea (yarrow), Alcea (hollyhock) – larval food, Allium (flowering onion), Arabis (rock cress or wall cress), Asclepias tuberosa (butterfly weed) and Asclepias incarnata (swamp milkweed) food for monarch caterpillar and nectar for many adult butterflies and moths, Aster – adult and larval food, Buddleia (butterfly bush), Caryopteris (blue beard), Chelone obliqua (turtlehead) – larvae and adult food plant, Chrysanthemum, Coreopsis (tickseed), Echinacea (purple coneflower), Echinops (globe thistle), Eupatorium (boneset and Joe-pye weed), Gaillardia (blanket flower), Helenium (sneezeweed), Hesperis (dame’s rocket or sweet rocket), Hylotelephium (upright border sedum), Lanvandula (lavender), Leucanthemum (shasta daisy), Liatris (blazing star or gayfeather), Malva (mallow) – larval and adult food plant, Monarda (bee balm), Phlox paniculata (garden phlox), Physostegia virginiana (obedient plant), Rudbeckia (cone flower), Salvia. Scabiosa (pincushion flower), Solidago (golden rod), Verbena, and Viola (violets) – food source for caterpillars.

Green Violetear Hummingbird

Green Violetear Hummingbird

Hummingbirds are one of the favourite inhabitants of the garden. The colours of our most prevalent hummingbird, the ruby throat, are dazzling when the sun reflects from their feathers. Hummingbirds are a delight to watch in the garden because of their child-like antics as they dance from flower to flower.

Hummingbirds will visit flowers of all shapes, colours, and sizes but they prefer tubular or trumpet-shaped flowers that are bright red, orange, and hot pinks. Tubular, red flowers often have more nectar than other types. Hummingbirds feed both on nectar from flowers and soft bodied insects such as aphids and small spiders from which they get much needed protein. Hummingbirds use a lot of energy for their aerial acrobatics and must eat huge quantities of food (insects) to survive.

It takes careful planning to attract hummingbirds to the garden and keep them there. Most important is the need for season-long blooms. Flowers must be open and ready for male hummingbirds that arrive in early May. The males arrive ahead of the females because they have a mission to establish their territory. Both male and female hummingbirds will stay until late August or early September. At this time they leave to go to their winter home in Mexico.

Some people feel that a hummingbird feeder is necessary to attract these birds. What is recommended is to put up a sugar and water feeder in May as a supplemental food source if blooms are scarce. This must be cleaned often (almost daily) during the hot weather so that the sugar does not ferment and potentially cause salmonella poisoning. With smart plant selection, a hummingbird garden can be designed so that a supplemental feeder is not required.

Designing a hummingbird garden involves consideration for hummingbirds need to access flowers from all sides. A garden that has plenty of hovering room so that hummingbirds can gain access to their favourite blooms is ideal. Do not crowd the area with dense shrubs and trees, although they do need some larger shrubs or trees from which to perch, rest, or use as a strategic lookout post.



When selecting plants, consider that the less hybridized the plant the more likely it will have a good nectar supply. The key to good nectar is to choose a wild or native species instead of a cultivar. The following perennials are known to attract hummingbirds. The common name is in brackets. Alcea (hollyhock), Aquilegia (columbine), Asclepias tuberosa (milkweed), Buddleia (butterfly bush), Chelone obliqua (turtlehead), Dicentra (bleeding heart), Digitalis (foxglove), Heuchera (coral bells), Hesperis matronalis (dame’s rocket), Kniphofia (torch lily), Lilium canadense (Canada lily), Lobelia speciosa, Lobelia cardinalis (cardinal flower), Lupinus (lupine), Lychnis chalcedonica (scarlet lychnis), Monarda didyma (bee balm), Penstemon (beard tongue), Salvia, and Yucca.

The introduction of a few wildlife-friendly plants can make a huge difference in the garden. Plan to grow some this summer.

Hummingbird images are from Wikipedia and used under the Creative Commons Attribution/Share-Alike License. All other images are copyright The Laptop Gardener.