I have 6 inch plastic drain pipe rolled around the very bottom, that small pvc at the bottom is an over flow for the pipe not to get over 3/4 full, I have the ends covered with garden material that lets just the water to set in the pipe, the pipe on top is where I water it,, it goes in the drainage 6 inch pipe,, fill with a good fluffy garden mix (potting mix) .. look up wicking system potting. Can't believe I didn't take pictures as I built them