Jim wrote: >> The problem is capillary action holding water in the fine spaces in the medium. Until the hydrostatic pressure of the vertical column of water exceeds the capillary attraction/surface tension of the water at the bottom of the medium, the water won't flow down and out. This is an interesting discussion. If I'm following correctly what everyone said, I wonder if the inverted cans might work better if there were no sheet of fabric placed over them. As long as there was soil around the cans, and the soil was uniform throughout the pot, would the soil around the cans draw down the water from above? Mike San Jose, CA