The Chicago Botanic Garden has released the results of the largest green roof plant study ever conducted in the United States. Five years of research on the green roof of the Garden Plant Maintenance Science Center has led to the publication of Plant Evaluation Notes highlighting the most extensive list of best plants for green roofs
“Ultimately, the success of a green roof is due to the success of the plants growing on it,” said Richard Hawke, plant evaluation manager at the Chicago Botanic Garden. “Plant trials like the one undertaken here are crucial to increase the knowledge about the best plants for green roof culture.”
A diverse group of 216 plants were evaluated in the extensive (growing depth of 3 to 6 inches) to semi-intensive (growing depth of 6 to 8 inches) green roof garden. Nine plants received five-star excellent ratings for their overall performance and survivability, including Antennaria dioica, Calamintha nepeta ssp. nepeta, Juniperus chinensis var. sargentii ‘Viridis’, Phlox subulata ‘Apple Blossom’, Phlox subulata ‘Emerald Blue’, Phlox subulata ‘Snowflake’, Rhus aromatica ‘Gro-Low’, Sporobolus heterolepis, and Sporobolus heterolepis ‘Tara’.
So now you know the best plants to use at your green roof if it’s located in a region similar to Chicago. If not, I’m afraid you should conduct a research yourself.
You can check the research here: http://www.chicagobotanic.org/downloads/planteval_notes/no38_greenroofplants.pdf
Photo by: Chicago Botanic Garden www.chicagobotanic.org