Sooo - I'm seriously considering a greenhouse. (will be adding India and probably Brazil to my travel schedule next year) But I live in a community where the homes have large patios with only a 2 - 3 ft rim of 'dirt'. So a greenhouse would have to be set up on the patio. It seems possible to me that if I had a heavy wooden base, say 4"w by ?"h of lumber, that I filled in with pea gravel, that would work. The patio is already slightly sloped to allow drainage, I would have to put some sort of outlet in the base to make sure water did not get trapped. Then attach the greenhouse to the wooden base.

So, existing concrete slab, add a layer of heavy plastic over the concrete. Wooden base 4" thick by 6 - 8- 10 - ? inches tall. Fill in with pea gravel, make sure the base has appropriate draining holes. Could bolt the wooden base into the concrete as well to avoid wind problems. Figure out how to run a gas line in for the heater - I have an outside natural gas tap for a bar b q, so that part is done - wonder if I would have to run the line underground from the tap to the greenhouse? Same with electrical for fans, pump, timers... Hmmm

What do you all think? Any suggestions, comments, personal experience, is welcome.