A new "garden calendar in the ground" in suburban Baltimore grows crops with relevance to Hebrew months in an effort to bring Jews back to their roots. The circular garden is divided into 12 sections, representing the 12 months in the Hebrew calendar.

Lessons also are taught on Sundays on Jewish agricultural laws, such as the prohibition of mixing two different kinds of seeds. "It feels like a lab, sort of," says Gabriel Greenberg, a farm educator. "We're reading this really obscure text and trying to put it in the ground."

Ten percent of the produce is donated to charity, in accordance with Jewish law.