Colorado State University’s department of Horticulture and Landscape Architecture has identified 5 plants optimum for green roof use in semiarid regions. This 2-year experiment proposed that plants native to the Rocky Mountain region may be ideal specimens due to acclamation to shallow, rocky environments.
Jennifer Bousselot, who led the research, says that other green roof studies focus on nonsucculents “Typically native to areas with high annual precipitation and relatively deep soil profiles”. Bousselot maintains that until this study, green roofs have not undergone scientific evaluation in semiarid environments such as Colorado.
One species tested, Kannah Creek Buckwheat, was removed from the study due to poor performance. The remaining five all tested well and can be considered for green roofs in semiarid environments, with blue grama and hardy iceplant leading the pack, followed by small-leaf pussytoes, brittle pricklypear, and spearleaf stonecrop.