Native Plants For A Green Roof
Green roofs are so popular in many parts of Europe, I would love to install one on my house. The cost of doing so, however, would almost certainly put me into the poor house. I’m not entirely sure how so many Europeans can afford to build homes with green roofs, but I do know that the technology here in Canada lags a bit. Unless built specifically with a green roof in mind, our homes’ foundations would have to be re-enforced just to accommodate the weight of all that dirt, water and plant life. Perhaps it’s just that Europe sports a more forgiving climate. Except, there are a lot of Canadian locales that are famous for temperate weather. Recently the Canadian Ornamental Horticulture Alliance (COHA) and Nova Scotia Agricultural College met at Vineland Research and Innovation Centre (Vineland) to assess plant diversity and survival issues for green roofs. They want to find out whether widespread use of green roofs is even possible here.
One of the main decisions that people who install green roofs have to figure out is what kind of plants should be used. Sedum is nice, but how hardy is it over the long run? “Multi-year survivability has been an on-going issue for green roof habitats in Canada,” said Dr. Rumen Conev, Vineland’s Research Scientist, Ornamental Plant Breeding. “With this research we are particularly interested in moving away from the more common plantings to a broader selection of native plants that demonstrate sun, wind, cold, and drought tolerance.” With over 20 new native species being studied, a green solution to making Canadian
buildings more energy efficient could be right under our feet. Those of you who eschew lawn maintenance, don’t worry; the grass populating your front yard isn’t one of the options here.
The environmental benefits of green roofs are already well-documented. Homes that have been outfitted experience significant reductions in building heating and cooling costs, storm water runoff management, and natural habitat creation. However, lack of research into planting options and managing green roof health in Canadian climatic conditions has been a barrier to growth — figuratively- and literally-speaking.
“Canadian cities are lagging behind in North American green roof rankings”, said Andy Kuyvenhoven, President, Kuyvenhoven Greenhouses Inc. and President of COHA. “Growers and nurseries have a suite of native plants that we believe can do the job. This research will confirm the best choices from dozens of species that are already highly adapted to and can help resolve the issues of the Canadian conditions.”
If you could, would you install a green roof?