I'm still in the planning stage of my first grow, but I was thinking about 1 gallon milk jugs with the top cut off. one plant per pot. they're a little under 12x12, and are square, so they should fit snugly together with not much space wasted between them. and they're free!
if you need bigger, maybe make make something. I love being creative. maybe some scrap wood. pressure treated will last longer, but not sure if it would hurt the plants. I have plenty of vinyl siding laying around, so maybe something lined with that. 2 strips tall might give me close to 12 inches deep, can be any size pot. wow, my ideas suck today. check at a local grow shop, or even walmart.
