I am planning to put in a vegetative roof on my house. It will be about 1,000 sq feet. I am planning to use daisy trays (10 X 20 Inc). For growing medium I am planning a combination of brick chips, crushed oyster shells, perlite, topsoil, and peat moss. for plans I am using seedum plants - 5 to 10 varieties. Does anybody have any expeirience with growing seedum or similar projects?