Another pinner says - I have made these before - so easy! Lowes sells the 4 to 6" round PVC pipe with holes already drilled. Purchase an end cap, fill with rock, soil, and plant. I will often put these in the center of a very large pot to stabilize, and add amazing height and color to a container that has trailing plants (no end cap or rock needed if you are placing in a container)
Could be put on top of a garden shed or near kitchen garden to keep well water use down. Rain barrels could be used to make a large self-filling chicken waterer by installing nipples into the PVC pipe. Water could come from the roof of the chicken coop!