what are you going to cover it with ?
I framed up a 12 ft x 25 ft greenhouse a few years ago. I planned on planting just on the ground inside of it. it worked well for a couple of years for tomatoes and peppers.
then I skipped a year. the weeds over ran it. I didn't use it this year because of the dense weeds. they do grow well in nice fertile soil, don't they ??
next spring I will have to go in and rototil with the big tiller if I want to use it..
tip: if you need to enrich the soil or add dirt, do it on the area before you build the walls. I didn't do that so now I have to haul any amendments in with a wheel barrow where I could have just used the tractor and bucket and filled it in just a few hours..
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