On the 2015 Shopper’s Guide of the Environmental Working Group (EWG) (which ranks fruits and vegetables contaminated by pesticides from most to least), blueberries grown in the United States came in at No. 14, while imported ones landed in 24th place. There’s another reason to go green: “Organic blueberries tend to be smaller because they don’t get as much nitrogen fertilizer,” says Mary Ruth McDonald, research program director of plant production systems at Ontario’s University of Guelph. There are more antioxidants in smaller blueberries. These five facts about wild blueberries will change the way you think—and eat.