Try sliding patio door panes or window pane units at Habitat for Humanity.
Ever hear of Google? Great place to look for DIY greenhouses.
id anchor that thing with more than some cinder blocks. once you put plastic on that thing its basically a giant kite.
https://www.youtube.com/watch?v=-v7FujAXg4Q
you have several options when it comes to plastic coverings.
https://www.agriculturesolutions.co...iffused-ir-ad-greenhouse-film-4yr-6mil-detail
good luck
First have to secure bottom to cinder blocks somehow. You can secure plastic by using cables across like an X. Or you can buy some that already have covers that fit:
https://www.amazon.com/King-Canopy-...TF8&qid=1485058419&sr=8-7&keywords=greenhouse
lol, yes i have had that experience i came outside and the entire greenhouse was in the neighbors
55 gal drum full of water weighs over 450 lbs. Put one on each corner for an anchor, even that's not enough really. A guy with a record kite in Oregon had to anchor off to a dumpster full of sand. He got caught in the line and died. Kite actually moved the dumpster.
Hey, this is going to be hard to explain, but i'll try my best
the metal tube frame looks like its 20 or 25mm (3/4 or 1") so get some electricial conduit that either , just slips over it, or is very close to fitting on.
cut the length of conduit into 1 1/2 inch bits and them take a slice out of them so that they are C shaped.
wrap the plastic around the frame and then push the C bits on to secure the plastic.
Hope that makes sense ? i'll try to find a pic of what i mean and post that