Urban agriculture actually dates back 10,000 years to the dawn of farming. Big cities arose alongside farms, not after them, according to an in-depth article about the origins of urban gardening by Tom Philpott on the environmental news site Grist. The past century's explosive growth created an artificial division between urban and rural, and today's garden hot spots in Brooklyn and San Francisco may, in fact, be a return to tradition:

Cities didn't just innovate techniques that would later become associated with large-scale, chemical-dependent agriculture, they also incubated sustainable ones. The so-called "French-intensive" method of growing vegetables -- in which large amounts of compost are added annually to densely planted raised beds -- is one of the most productive and sustainable forms of organic agriculture used today. And guess what? It developed not in the countryside, but rather within the crowded arrondissements of 19th century Paris. Maine farmer Eliot Coleman, one of the leading U.S. practitioners of the French-intensive style, credits those pioneering Parisian farmers with ingenious methods of extending growing seasons that are only just now coming into widespread use in the United States.

The French-intensive method hinges on a principle identified by Jane Jacobs, one that modern-day city residents (and planners) should take to heart: that cities are fantastic reservoirs of waste resources waiting to be "mined."

Read the full story at Grist.