In my experience it depends a lot on where you live. I'm in Cambridge and driving to, for example, Brookline, isn't worth it. But one really appealing option I've been considering is Boston Organics (Boston Organics: Delivering Fresh Organic Produce to Your Door!
). They do delivery and are even bonded to hold a front door key, should you want to have them drop it off during the work week. Prices seem to start around $24/month, and you can opt for weekly, or every-other-week delivery. But I have not yet tried it, myself.