I'd like to try to grow strawberries in large pots on our deck this summer. The recent Gardener's Supply catalog is offering self-watering adapters that can be placed in the bottom of pots, with a tube going up the side to add water. Has anyone out there tried these?
Those "self-watering" pots and the like are very expensive and not very effective. On effectiveness first --it will be YOUR-self who waters them. Just because you put in an extra quart or gallon doesn't mean they won't dry out. Even if the extra water provides the proper moisture level consistently --let's assume it does-- if you are lulled into thinking you don't have to water, you got trouble.
I also think that tapla will say a.) the better use of the pot-space the devices occupy, at the bottom of your pots, is best used as more space for soil in which roots can grow, with proper watering and b.) these things don't change the laws of physics --you'll still have a PWT level, it'll just be higher up in your pot by the exact depth of the water level in the device.
On expense --for the price of two of those pots, $25, you can put together a simple irrigation system that will let you water all your plants in a couple minutes each day. For the price of five or six, you can put one together with an automatic timer that provides two different timing/amount patterns.
Overall, with proper watering (by and or by irrigation), you and your plants will be better off with good soil to the bottom of your pots instead of an expensive, hidden reservoir where roots could otherwise be growing.