The following (green) retail and coop grocers sell locally grown organic produce:

Glut Coop Mt Rainier, MD Takoma Park Silver Spring Food Coop Takoma Park, MD Bethesda Coop Cabin John, MD Roots Market Clarksville, MD Common Market Frederick, MD Washington's Green Grocer Delivering organic produce to your door throughout the Metropolitan, D.C. area since 1994. My Organic Market Located in Rockville & College Park, MD as well as Alexandria, VA.  Great prices and huge selection of groceries! The Epicurious Cow Amissville, VA.  While located 75 minutes from downtown D.C. in Rappahanock County, VA., this oasis in the middle of some of the most beautiful local farmland is definitely worth the drive.  I recommend having an award-winning dinner at http://www.theinnatlittlewashington.com/ and spending a cozier and less expensive night at http://www.gaystreetinn.com/, both in (little) Washington, VA.