If you are like us here at Mirage Landscaping, Calgary’s commercial and residential landscaping company, you want to know which plants will best serve to make your home lush and beautiful during the growing season.
Alas, as with most things, figuring out which plants thrive the best in Calgary turns out to be a complicated issue. Let us leverage our three generations’ worth of experience serving our Calgary area clients to examine some of the factors that influence what will grow and thrive in your backyard.
The foremost variable in determining what will grow and what will die in your garden is our climate in Calgary. For the purpose of planting, the government of the United States invented what are called “Hardiness Zones” that take the climate information accumulated over the decades to detail where certain plants should thrive better than others. The Canadian government has taken this same approach and tailored it to our climate, though you will readily see cross pollination between the two systems on the Internet, so take care that you are reading a Canadian specific table, map, or whatnot.
Nevertheless, such maps are only a rough guide. There are so many other factors that go into what plants might thrive on your own property that they bear mentioning. Elevation is major factor in Calgary. Differing elevation, when coupled to data about wind exposure, average snow cover, etcetera, makes for local “microclimates.”
Microclimates in Calgary
Most modern historical weather data in Calgary was collected at Calgary International Airport, sited at 1084m above sea level. Looking at the city, its highest point is at 1295m and the low point is at 975m, making it critical that you know the elevation of your property. With 300m in elevation change, properties in northern and western Calgary face more rapid cooling at night all year round, and more rapid frosts when atmospheric moisture is high. As you approach the flood plain of the Bow River, the presence of the river itself makes for a more moderate microclimate, assisted by the fact that Calgary’s concrete and asphalt are a heat island across which the prevailing wind blows.
The main focus of the planting zone concept is whether the weather is severe enough in winter is capable of killing an overwintering plant. The good news from such sources is that most of Calgary is in planting Zone 3, which still affords a wide range of ornamental plants. However, microclimates in parts of the Calgary area can take you down to Zone 2 or up to Zone 4.
No matter your planting zone, if you have decent soil and sunshine conditions, you will always be able to grow annuals and vegetables if you plant after last frost in the spring and harvest before first frost in the fall. The Canadian hardiness zone information was originally developed as a guideline for trees and then gradually adapted to perennials by including the number of hot days, the average winter snow cover and other factors. Once you know the elevation, prevailing wind, and other variables particular to your property, you can begin to determine what perennial plants your site is capable of supporting.
Generally speaking, in the climactic zones that prevail in Calgary, three characteristics mark the kinds of perennials that thrive here. The first type that survives the “killing frost” of Calgary are the ferns, whether flowering or not, because they go dormant for the winter. Many flowers which grow from bulbs can be planted below the expected winter frost depth and will be hardy in Zone 3 come spring. Finally, any perennial that can sink deep enough roots, such as shrubs which are considered “cold hardy” can be planted here, and will be aided somewhat by the heat radiating from your house’s foundation if you plant it close to the house.
For an ornamental garden, you want to have a mix of plants to ensure something is always in bloom between late May and mid-September. If you select flowering ferns, roses adapted to the climate, daffodils, tulips, western Canadian violets, yellow foxglove, Jerusalem sage, and other plants that will thrive in your Calgary area backyard you can have a garden oasis until the first hard frost turns the late bloomers to dormancy.
However, if you want the garden without all of the hard work of site determination, preparation, planting and season long care, you could consider hiring us instead. We have decades of experience determining what will, and won’t survive throughout the microclimates of Calgary.
If you have a project in mind to beautify your property, we can assist you through every step of the process. From design, to plant selection, to fall and spring planting, we are a full service commercial/residential landscape and lawn maintenance firm who are always willing to give you a free quote.