A couple of years ago, I was doing research on building do-it-yourself self watering pots- where there is a resevoir of water on the bottom of the pot, and through capillary action, the water wicks up through the soil, keeping the pot evenly moist. there are numerous designs, Gardener’s supply company sells the Earthbox, and people have posted other designs. with rubbermaid tubs, or recycled recycle bins. The one thing they have in common is they are butt ugly. I have spent money on pretty blue ceramic pots, and I don’t want to uglify my yard…
I did pay for one liner, from gardener’s supply, and thought about making more with bowls, and mesh, and PVC pipe…the whole idea made me tired.
Then I saw these terra cotta vases at Hobby Lobby- about 6 inches across, 10 inches tall, no drainage hole in the bottom, but unglazed, so they are porous. They hold about 2 liters of water.
I bought one to start, and put it in a 14 inch pot, and put geraniums into the pot. They did great. The soil stayed evenly moist, and I was able to put a smaller pot on top of the vase, too. Roots dangled into the water from above, and water continually seeps through the pores of the terra cotta. If you pour a half gallon of water into the soil of a regular pot, most of it drains out the bottom, and you need to water again the next day. Under my conditions (arid west, bright sun, YMMV) I can fill the resevoirs once or twice a week.
I now have 3 or 4 of the vases- they aren’t great for everything, and they need to be covered with either a plant or a saucer so mosquitos don’t breed in the water. I have read about them being used in raised beds, also, but have never tried it. If your craft emporium doesn’t carry them, check thrift stores- I’ve seen terra cotta wine coolers every once in a while that would work pretty well, I think.