Drip-it Pro Waterer (see May 11, 2008 post) was designed for house plants. I tried it with my vegetable container plants this summer. I have one in a pot of pole beans and one in a pot of cucumbers.
I filled the water containers about once a week. The 8” water bottle holds about 4 cups of water. It is simple to fill and use. The T-shaped “wick” sometimes fell out as I put the pronged cap on. But, they were easy to put back in place.
I still had to water once or twice a day in the summer heat. The water bottle may have helped keep the pots from completely drying out.
I think they will work for my large house plants while I’m on a 2-week vacation this winter.
Gardener’s Supply “2-Week Plant Sitters” http://www.gardeners.com/Drip-It%20Waterer/17519,default,pd.html