Liz Whitehurst dabbled in several careers before she ended up here, crating fistfuls of fresh-cut arugula in the early-November chill.
The hours were better at her nonprofit jobs. So were the benefits. But two years ago, the 32-year-old Whitehurst — who graduated from a liberal arts college and grew up in the Chicago suburbs — abandoned Washington for this three-acre farm in Upper Marlboro, Md.
She joined a growing movement of highly educated, ex-urban, first-time farmers who are capitalizing on booming consumer demand for local and sustainable foods and who, experts say, could have a broad impact on the food…