Red Butte Garden has a new green roof! Come check it out. Its great design is composed of four varieties of Sedum and one variety of Sempervivum all flowing together.
The planting medium used is called Litetop® Soil. It is a specially blended lightweight growing medium composed of organic and mineral material. It retains moisture for plantings, yet drains excess water quickly and doesn't compact.
For those interested in the plant varieties used the list includes: Sedum rupestre 'Angelina' (lime green patches), Sedum hispanicum 'Purple Form' (gray-green patches adjacent to lime green patches), Sedum spurium 'Voodoo' (reddish patches), Sedum kamtaschaticum (dark green patches in three of the corners), and Sempervivum 'Commander Hay' (patch of plants in the very center of the roof)