Lagniappe

Some may consider it a 'gateway' fish, one which leads to the angling of larger, more dangerous fishes.

I've thought up several designs for hydroponic banana planters and all would be great.....for a greenhouse. The problem is I can't figure out how to keep the rains from diluting my nutrients or overflowing the whole system outdoors. I've considered a layer of plastic over the pot which the banana grows through. Any suggestions?