Gardening Where There is No Soil

If you live in New York City, you probably think I'm talking about your apartment: how do you make green things thrive where there's no dirt for their roots to grow?  Taking a page from the Floating Islands of Peru, I would suggest a raised bed system.  In your apartment, that might mean yogurt containers filled with dirt teetering in your bathroom window, but when my sister and I visited Lake Titicaca, we found what I think to be one of the world's most inovative gardens (outside of the parking lot plots in Red Hook, Brooklyn).  These islands float on a cross-webbing of spongy lake reeds. To walk on them is like walking on a waterbed in a canoe.  A small patch of carefully imported dirt (rowed in from the shores of Puno, Peru) hosts young potato plants.  Other food sources include a pond full of previously captured fish.  In fact, the young reeds themselves can be gnoshed, with the not totally unpleasant taste of wet styrofoam dipped in sugar.