At Coastal Maine Botanical Gardens (USDA Zone 5), where I work, there is an information kiosk with a wooden shingled roof. I am going to plant it and am wondering if anyone had had experience doing this type of project. It's about a 45 degree slope, so I plan to place a layer of Promix (perhaps mix in some of those polymer granules that soak up water) with a layer of live sphagnum moss over that to help hold the potting mix in place. I will then put a sheet of that black plastic mesh netting over the entire surface and fasten it down on the edges. I'll cut holes in the mesh where I want to insert plants. Since this may only receive water when it rains, I need to select drought-resistant plants. Sedums, sempervivums, other succulents and chives have been recommended.
Can anyone make offer any suggestions or make any recommendations? Also, can anyone recommend a source for inexpensive succulents?