I have been using plant caddies on some of my outdoor plants, usually the metallic ones. It makes fall clean-up a lot easier for me. I got mine either from Home Depot or Walmart. Sometimes it comes with a plastic container too, but I just remove that plastic part so the water will drain easily. Indeed, this plant caddies are very effective, especially with the big vases that I use, just make sure to measure the diameter of the caddy well, you would not want your vase to topple over when there are strong winds, if the caddy is too big for the vase.