Why is it so darn hard to grow things in Calgary and why do our BC friends shake their heads at our landscape struggles?
Calgary is on the eastern slopes of the Rocky Mountains, which have a strong influence on our weather as well as our climate. We are in the transition zone between the prairies and the foothills, and as a result, we have influences of both climatic regions. We have the drought of the prairies with the rain shadow of the mountains. Add in the cool nights of the foothills, combined with the Chinook phenomena, and you have a recipe for challenge.
After many years of growing and testing a vast number of plants, we have determined that our major limiting growing factor is the cool summer nights. Although we might enjoy them, it makes it difficult for those plants that are programmed to grow in areas of more moderate night temperatures. Plants that are less hardy will often experience a premature shutdown of systems, which can delay maturing of leaves, hardening off of new tissue, and ripening of fruit. A plant which does not mature all of its system will face massive struggles when winter does hit. If plants are not shutdown properly, there will be winter damage – which will manifest as tip kill, lack of vigor, and insect or disease infestation in the next growing season.
Plants that have evolved in this climate are genetically programmed to survive and thrive. They break bud, flower, grow and fruit, then shut down properly in preparation for the long dry winter.
Healthy plants are more drought resistant, disease resistant and insect tolerant. Better seed sources will result in better plants – the native plants actually like it here.
Native plants are those which existed prior to European settlement. Introduced plants are those which were brought from other places like Europe, Asia and Siberia. At Bow Point, we can recommend the best native substitutions for popular introduced plants that will thrive in our local climate, and give you a landscape that will thrive with little maintenance for years to come.
Alternative to Cotoneaster: Originally from Asia, it is hardy in this area, but does have a multitude of problems like pear slugs, fire blight, and oyster shell scale. Try Powderface Willow or Red Twig Dogwood as an alternative. Both offer disease resistance, and are insect tolerant and more winter attractive alternatives.
Alternative to Caragana: From Siberia, a very hardy shrub meant for the prairie shelterbelt programs. Although it has worked well in that respect, there is some concern as it spreads into Banff National Park and chokes out the native species. A better alternative for a large drought tolerant wind break plant would be the native Silver Buffaloberry. Buffaloberry provides better bird and small animal habitat, is not invasive to the exclusion of other species, and shows greater drought tolerance than Caragana.
Alternative to Spruce: Spruce, whether it is Colorado, White, or Norway, all grow very well in Calgary, if they are of good seed sources. Sometimes they grow too well and often can over grow a site – our firewood pile is a testament to that. Spruce form a solid wall – without dispersing wind or sound. A good alternative is to plant Pines – Lodgepole, Limber, or Ponderosa – which are more open with finer texture – they tend not to over grow a site. In our opinion, they are a better choice for smaller yards.
Alternative to Swedish Columnar Aspen: Why plant a too-narrow tree that everyone else on your block has? Especially one that may succumb to disease down the road. A great alternative is the River Birch. You still get that slender, narrow footprint. But, you also get a great bird feeder, distinctive red bark for an striking winter look and long-lived hardiness.