On a corner in Washington, D.C., where stores burned during riots 44 years ago, there's now a plaza where farmers sell produce on Saturday mornings. Dan Charles/NPR hide caption

itoggle caption Dan Charles/NPR

Georgia O'Neal harvests winter greens at the Tree and Leaf Farm in Unionville, Va., on March 16, 2011. Maggie Starbard/NPR hide caption

itoggle caption Maggie Starbard/NPR

Desmond Brown sells fruits and vegetables at a farmer's market outside the Alabama Capitol in Montgomery, Ala. Dave Martin/AP hide caption

itoggle caption Dave Martin/AP

The regular old supermarket is still king for choice, price and convenience

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itoggle caption Bart Sadowski/iStockphoto.com