A reader asked me about using a five gallon plastic bucket instead of a store bought system, and the quick answer is yes you can. Drill two inch holes in the bucket, either in the side or on the bottom. Cut a piece of sponge wider than the hole to cover the drilled holes enough to keep the potting soil from washing out. Before placing the sponge in the bucket permanently make a cut 1/2 way through its diameter so that the plant stem can pass through the slit, but once the plant begins to grow, the stem will have room to expand.
I would also reinforce the bucket handle if it is too flimsy to support the weight of the plants, the gardening soil and the water. I have seen picture hanging wire used for this. But I would be sure and drill the holes for the wire instead of punching them and attach by tying the wires to a flat washer to keep from pulling back through the drilled hole. At this point you can decorate or paint the bucket with your kids or use your bucket “as is.”