When my fiance comes home with zucchini in December, a tiff always ensues. "That's a summer squash!", I scoff. "But it'll go great in the stir fry," he retorts.
There's really something to be said for eating produce that is grown not only within a hundred or so miles from your house, but also when it's supposed to be grown. Tomatoes? Well, sorry, but you're just not supposed to be eating fresh tomatoes in January, not if you live anywhere in the northern hemisphere (and based on landmass vs. water distribution on the planet earth, you probably do). Do you really want a vegetable that was grown hydroponically, picked when bright green, shipped a few thousand miles, and then ripened with ethylene gas? Because if you're eating a January tomato, that's what you're getting.
The bottom line? Local, seasonal, and preferably organic produce will taste best and be the best for you. And it's often the best value as well - it costs money to make plants do what they don't want to, and that cost shows up in the consumer's pricetag.
So, why not go for the butternut squash instead? The cabbage, turnips, and potatoes? And if you want a little tomato-ey kick during those long winter months, you can get really industrious - take those ripe summer tomatoes and can them (this can also mean jarring) and then you'll have them in winter as well. After all, there's nothing wrong with frozen and canned vegetables! Just so long as you're eating plenty of fresh ones as well, of course.
Great! But... what is in season when? I've known that it's best to eat seasonally for, oh, just ages now. Trouble is, though, that I rarely have the time or energy to get down to the utter and complete madhouse that is the Union Square farmer's market. And as odd as it sounds, CSAs in my area are actually rather competitive and hard to get into. So how do I know what, in fact, is in season?
Luckily, we've got the internet! And there are fine people who have compiled this information for us. There are charts for fruits and vegetables available from the BBC that are a great jumping-off place. And don't be a wimp like me - if your town has a farmer's market, get down there and support it! CSAs are also of course a great way both to support local farmers and ensure that you're eating nothing but fresh, seasonal produce. This post on The Sustainable Scoop goes into more detail on the whole eating locally gig, if you're looking for a bit more inspiration.
So there you have it darlings. Make 2010 the year you start eating seasonally!