Inverted gardening
A method of growing plants in a hanging planter where the rooting medium is suspended above the plant, so that the plant grows downward. Used for growing tomato plants indoors. [photos] [google]
Topsy Turvy
A commerical product is available, Topsy Turvy. [old]
“Tomato-Growing Device Turns World of Gardening Upside Down, Had Appeared on QVC” [archive]
Making your own inverted planters
There’s a number of articles on DIY methods. One simple, effective way is to put a cherry tomato plant through the bottom hole of a plastic hanging planter, fill it with dirt and plant parsley on the top of it.
Some use plastic 2-liter soda jugs and mount them to stakes outdoors.
“Inverted Indoor Gardening” was a 2006 article on making an indoor planter according to this method. [archive]
Another DIY guide to doing this.