Instructables user shellberry made this how to on urban gardening. From the site:

We’re turning the concrete jungle backyard of our townhome into an experiment in sustainable urban homesteading. Here’s how you can add some OCD (i.e. easy to maintain) gardening space using an adaption on Mel Bartholomew’s Square Foot Gardening practices (build up, don’t dig down and organize in sq. ft.). Super easy, lots of fun.

Via the Instructables Weekend Builder