Tips for surviving in the clay belt
“All human wealth is from the earth.”
— Margaret Atwood
As the glaciers passed through here 10,000 years ago, they did us some great favours. For one, the Great Lakes were carved out of the hard earth providing us with an abundant source of fresh water that should last forever, if we don’t botch it up. They also left us with superior soil in the southwestern part of the province that is, for the most part, rock free and of such a fine, sandy/ loamy till that soil lovers anywhere would fall to their knees, scoop it up in their hands and breathe deeply the wonders of life that thrive within.
Alas, here in the GTA, most of us are blessed with clay-based soil that is great for pottery and bricks, but when it comes to growing a great garden all we can really do is try our best to change the quality of the clay and to live with it. Once again, I am here to help.
If you happen to live in the clay belt, there is some good news. First of all it helps to understand why clay-based soil is tough on most plants. The soil particles of clay are very small and they stick together like glue. When clay is wet it sticks to your boots, when it is dry it sticks together.
Breaking up clay particles is no easy matter. One of the best amendments is good old-fashioned sand. Look for builder’s sand or play sand (for the sand box, not beach sand). Coarse builder’s sand will open up the pores of the clay providing much needed space for oxygen and water to flow through.
Another useful amendment to clay soil is gypsum. There is a chemical relationship between clay particles and gypsum that creates a more desirable environment for plants to grow. Take my word for it.
Mound good quality soil up to your plants rather than planting them deeply in the ground. Digging a hole for a plant in clay is not much different than planting in a bowl. Great for holding your cereal and milk but not so good for root development. Planting on a berm or raised garden also works. Just be sure to use good soil in the first place. Encourage drainage by trenching, or installing drainage pipes so you can help to move water from soggy, clay areas.
CLAY TOLERANT PLANTS
There are a lot of plants that tolerate clay soil. Few actually thrive in it, but as always it is best to take our cue from Mother Nature. Check out my list of clay tolerant plants below and note that there are other tactics that you can employ. Trees
Silver maple ( Acer Saccharinum): Grows quickly and does not know when to stop.
River birch ( Betula Nigra): A fine ornamental tree with bark that will eventually turn white.
Hackberry ( Celtis): A native tree that grows slowly but is worth the wait.
Common honeylocust ( Gleditsia): The “Black Locust” is a bit dirty as it drops branches and seed pods at the end of the season, but it makes up for it with its naturally high reaching branches.
European larch ( Larix deciua): A deciduous evergreen that grows quickly. I like the look of a grove of larch.
Bur oak ( Quercus macrocarpa): Another slow growing native but with luck your grandchildren will sling a hammock in it. Tall and rather narrow growth habit.
White cedar ( Thuja occidentalis): Yes, the same evergreens that we use to plant permanent hedges. Versatile, fast growing and a nice specimen as a tree or as a hedge (with annual trimming of course). Flowering Shrubs
Serviceberry ( Amelanchier): A native shrub that is first to bloom in spring. Attracts birds to its fruit later in summer and early fall.
Quince ( Chaenomeles): Fruiting quince have attractive flowers in early May and the fruit, which is much like an apple in appearance, is a great freshener for your fridge. Cut it in half and use it instead of baking soda.
Cotoneaster ( Acutifolia): I don’t know why we don’t plant more Peking cotoneaster. It is entirely winter hardy, features attractive glossy green leaves, white spring flowers and fruit that cardinals and cedar waxwings enjoy. Grows to about four metres unless you trim it down.
Forsythia: The yellow, early spring flowering shrub that we are all familiar with.
Canadian holly ( Mahonia): A deciduous evergreen, it drops its leaves in the spring as new growth develops; fascinating. Birds enjoy the fruit, clusters of yellow flowers in June.
Highbush cranberry ( Viburunum opulus): A native that flowers nicely in May, produces an abundance of attractive berries that birds like come March, after hanging there all winter. Flowering Perennials
Yarrow ( Achillea): Likes the hot dry sun.
Anise hyssop ( Agastache): Also loves the sun.
Marsh marigold ( Caltha): A woodland native plant that enjoys cool shade
Purple cone flower ( Echinacea): Loves full sun, great butterfly plant while in bloom and attracts songbirds when in seed.
Day lily ( Hemerocallis): It attracts hummingbirds. Needs mostly sun to thrive.
Bee balm ( Monarda): A native that loves the sun and attracts hummingbirds.
Planting in clay is not a lost cause; it just demands that you follow the yellow brick road to a great looking garden. Or you can dig all of the clay out and start again with quality triple mix. As I say, if you need a pickaxe to dig it, you probably should remove it.
QUESTION OF THE WEEK
Q: I have many iris plants and this year there are many fronds, but few flowers. How can I get them to produce more flowers? A: There are a number of reasons why irises may not bloom:
Sun: irises need at least six hours of direct sun each day.
Exposure to high nitrogen fertilizer: avoid spreading lawn fertilizer near irises.
Moisture: irises may not bloom if they experience a dry period during flower bud production.
Overcrowded clumps stop blooming until they are divided.