I can't remember if I've posted this before, and if I have, I apologize. My brain's a bit fuzzy from a busy week at work.
Anywho, here's an interactive guide to seasonable vegetables and fruits by Real Simple. You pick the season, it shows you what's best to buy. Click on the picture of the fruit or veggie and you get tips on how to pick out the freshest selection, how to store it, how long it will last and preparation suggestions.
Just looking at the pictures, I vote for summer fruits and veggies. Yuuuum.