This pot has onion sets in a double row around the terra cotta resevoir. A 4" pot with salad greens goes inside it.
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.
Strawberry Fields for Breakfast 
May 10, 2012 @ 22:34:20
Nice to see your double clay pot!
I have been promoting and working with clay pot irrigation for almost
30 years and am delighted to see them getting used more around the
world.
Cheers
David Bainbridge
San Diego
More clay pot irrigation info TM Stein has a biblio in line at Sakia.org
Bainbridge, D. A. 1986. Pitcher irrigation. University of California,
Dry Lands Research Institute, Riverside, CA 3 p.
Bainbridge, D. A. 1988. Pitcher irrigation. Drylander 2(1):3.
Bainbridge, D. A. 2001a. Irrigation and surface mulch effects on
transplant establishment. Native Plants Journal 2(1):25-29.
Bainbridge, D. A. 2001b. Buried clay pot irrigation. Agricultural
Water Management 48(2):79-88.
Bainbridge, D. A. 2002. Alternative irrigation systems. Ecological
Restoration 20(1):23-30.
Bainbridge, D. A. 2006. Beyond drip irrigation – hyper efficient
irrigation systems. Proceedings ASABE Annual International Meeting,
Portland, Oregon. ASABE #062073. St. Joseph, Michigan 10 p.
Bainbridge, D. A., M. Fidelibus and R. MacAller. 1995. Techniques for
plant establishment in arid ecosystems. Restoration and Management
Notes 13(2):198-202.
Balakumaran, K. N., J. Mathew, G. R. Pillai, and K. Varghese. 1982.
Studies on the comparative effect of pitcher irrigation and pot
watering in cucumber. Agric. Res.J. Kerala. 20(pt2):65-67.
Mondal, R. C. 1983. Salt tolerance of tomato grown around earthen
pitchers. Indian Journal of Agricultural Science 53(5):380-382.
Reddy, S. E. and S. N. Rao. 1980. A comparative study of pitcher and
surface irrigation methods on snake gourd. Indian Journal
Horticulture. Bangalore 37(1):77-81.
Sheng Han, S. 1974. Fan Sheng-chih Shu: An Agriculturist Book of China
written by Fan Shengchih in the First Century BC. Science Books,
Peking. pp. 36-37. (this got me started)
Stein, T.-M. 1998. Erarbeitung und überprufung von entwurfskirterien
für Gefäßbewässerungsanlagen. Journal of Agriculture in the Tropics
and Subtropics. #66. 174 p.
(this is excellent if you read German)
May 11, 2012 @ 03:06:48
Cheers to you- I somehow thought I had invented it, but then I started researching it and found that it is old technology. Thanks for stopping by!
Sep 08, 2012 @ 10:22:30
I cannot express how seriously thrilled I am to have found this idea! I’ve been struggling very much with figuring out how to make home-made self-watering pots in the cheapest most recycle-friendly way possible. I LOVE your example of an “inside-out” self watering pot. I’m so doing this asap.
ps. I, too, had only discovered recently that un-fired clay jugs without handles can be used to deep-water plants when it is buried up to the neck in the garden, by just adding water in to the top. Apparently this is an old-fashioned way of doing it, but I think it’s fantastic! The water just seeps through the clay just right apparently. I was unable to find clay jugs that weren’t fired, and they were all horribly expensive – your clay pot idea is perfect to me!
Thanks & best wishes 🙂
Sep 09, 2012 @ 21:31:56
I’m so glad this helped- it seems like I have seen unfired clay jugs at craft stores, but they were horrendously expensive- I couldn’t see spending 60 dollars on something to bury in the soil! The clay vases work pretty well for me, at 2 dollars each:)
Sep 08, 2012 @ 10:36:54
I meant un-glazed clay, not un-fired clay ~ Oops, I was so excited ! Thanks again, really fabulous idea!