The best way to find out is to know your local area, so find a few food stands that you trust and get to know the grower. Farmers are a pretty tight community, and if they don't have it, they'll let you know who else is growing it. Joining a CSA is also a good idea too, we have quite a few in Lancaster. The Simply in Season cookbook is also good. The best thing to do is just pay attention at market from week to week, because the variation in weather means some things may come in early or late. I'll try to keep this blog current with what's good and in season.