The key to ensure successful gardening of Calgary perennials in our northern climate, you must pay particular attention to proper planting techniques. A basic rule is that spring is the best time to move or plant in your perennials to make sure your roots get a good start and are strong enough to growth through a full season before winter sets in. Planting in the fall will lead to winter damage to roots that didn’t get enough time to get strong.
Spring planting is best for plant roots
It is especially important to plant evergreens in the spring because the time between the first leaf dropping in the fall to the first frost of winter, which has been known to come to Calgar as early as October, is s very short. An evergreen planted in the spring will be stronger before the first leaf falls and will maintain through a harsh winter season.
The long springs we get in Calgary can make us eager as gardeners to get out and start planting. While some hardy plants can be started as early as late April, a common rule for planting Calgary perennials is to wait until after the long weekend in May. This way we know the frost is out of the ground and we can be sure that the ground is ready to hold adequate moisture to help plants germinate.
Of course to every rule there are exceptions and certain Calgary perennials, like peonies and hardy lilies, can be planted in the fall. This is also the time to transplant them. Bearded iris, oriental poppies and bleeding-hearts also prefer to be planted and moved early in August.
Long blooming Calgary perennials
There are many Calgary perennials that have particularly long bloom seasons. The following list are some of the more beautiful flowering plants that stay in bloom from early summer to frost:
Veronica Whitleyi, a ground cover that starts blooming with the tulips,
Delphinium Grandiflorum or Chinese Larkspur, the royal blue of these flowers attracts hummingbirds.
Western Canada Violet,
Corydalis Lutea, a shade loving flower,
Symphyandra Hoffmannii, also called lady’s mantle,
Aquilegia Vulgaris, they bloom throughout the summer here,
Clematis Integrifolia, fern-leafed bleeding hearts,
Tiarella’s, Lamium, repeat-blooming shrub roses
The following are more Calgary perennials that also have long blooms but start a bit later in the season:
Primula Florindae and Alpicola both bloom from midsummer to fall,
Digitalis Grandiflora, perennial yellow foxglove,
Heliopsis Helianthoides, repeat-blooming daylilies,
Potentilla, the shrubs,
Sea Holly gives the impression of long bloom because the flower dries and looks fresh all season
Many types of asiatic lilies and daylilies, have different bloom times that range from early June to mid September and add colour to your garden throughout the summer.
You can also mix and match other Calgary perennials that have a shorter season and bloom at different times of the summer. Arrange these plants together so that their bloom times compliment each other that way there is always a good variety of colour in your garden.