Greenhouse: Planting Bed in Greehouse floor., 0 by stressbaby

stressbaby wrote:
Keywest, I wouldn't bother with the 18" deep foamboard. You just risk drainage problems.

Just do the perimeter. As we discussed elsewhere, studies of heat loss show only 2-3% through the perimeter of the floor, with the vast majority going through the roof. I have 18" deep beds in my GH and the plants grow like weeds in there. Here is a pic. The ground level bed is in the foreground. It is raised about 6"