Rooftop gardens or green roofs are becoming more prevalent these days, thanks to the tangible benefits people derive from them. These green roofs provide a layer of insulation that keeps the cold away during winter and heat from your house during summer. Green roofing Phoenix also give you beautiful hanging gardens filled with pretty flowers and visited by friendly insects and birds throughout the year.

Companies offering to build rooftop gardens are proliferating everywhere, although creating rooftop gardens is doable by those who prefer to do-it-yourself. Rooftops, however, are hostile sites for plants. They have to thrive on thin layer of soil and are constantly exposed to harsh elements, including strong winds, intense heat and cold and extreme weather fluctuations.

Selecting plants for green roofs require careful consideration of the location, substrate used, climate, maintenance and other factors. Usually plants that grow on desert cliffs, alpine crags and other inhospitable places are picked for planting on green roofs.

Plant Selection According to Purpose

Aesthetic Value

If the main purpose of the rooftop garden is aesthetic appeal, choose plant species that are physically appealing the whole year in terms of flowers and foliage. Among the favorite by homeowners are the succulents, which are commonly found on many green roofs or rooftop gardens. They come in a variety of colors and enhance the physical appearance of green roofs. They are also easy to maintain since they thrive with very minimal soil and water. These plants may be used for this purpose—ornamental Allum species, Agastache rugosa and Leonotis leonurus.

Drought Tolerance

For rooftop gardens designed with little or no maintenance required, plants that survive on harsh dry conditions are the best candidates. These are plants that are found in ecosystems with thin soils such as those found on rock outcrops. Their capability to survive long periods of dry weather by using water after rainfall is already proven. These plants are known to re-sprout after extended droughts. Some of these species include Stypandra glauca, Arthropodium milleflorum and Dianella revolute.

Water Management

For roofs designed to absorb water and eliminate contaminants in the water after storms, plant species that easily soak up water and absorb nutrients are preferred. Herbaceous and shrubs are more suited for this than the succulent species commonly found on rooftop gardens today. These herbaceous plants facilitate the movement of water from the roof into the atmosphere and help cool the surrounding areas.