What's so special about heirloom tomatoes? In a world where flavor and color are sacrificed for uniform, homogenous tomatoes bred for their ability to withstand the rigors of long-distance shipping, locally-grown, proudly diverse, and shockingly flavorful tomatoes are a precious rarity. And they're worth the wait. We are willing to forgo fresh tomatoes (often sad, forgettable rounds of pale pink on a sandwich or in a salad) all year for the pleasures of a sun-ripened, carefully-tended real tomato, either tart or a little sweet, dripping with juice and full of character and complexity. Farmers have their favorite varieties, and they'll tell you all about them. Here's a list of some of our favorites we've spied recently at SFC Farmers' Markets--now is the time to visit, try them all, and choose your favorites!

• Black Krim - Dark reddish-purple, juicy heirloom tomato from the Black Sea area in Russia. Tangy, rich, and sweet.
• Brandywine - A big, beefsteak, "pink" tomato, dating back to 1885, Brandywines are fantastically sweet with a mild acidity.
• Cherokee Purple - An old Cherokee heirloom with a deep, dusky red hue; sweet, dense, and juicy.
• Green Zebra - Bright chartreuese with darker green stripes, these tomatoes are rich and sweet with a tangy zing.
• San Marzano - An Italian heirloom, first grown in the volcanic soils under Mt. Vesuvius, San Marzanos are a "paste" tomato, best for making sauce.
• Sungold - Actually a hybrid and not an heirloom, we included them here because their thin skins mean you probably won't find them in the grocery store--and because we love them so. These small, bright tangerine-colored cherry tomatoes are explosively sweet and flavorful--we guarantee you can't eat just one!