Each spring Spencer Huey brings thousands of homegrown heirloom tomatoes to a parking lot in Berkeley, California, for a one-day community sale. “I grow 50 varieties of tomatoes and 2,500 plants,” says Huey, a cook at Chez Panisse and creator of the Tomato Club substack. “It’s a little crazy.”
Fortunately, there are plenty of enthusiasts who share his devotion. As temperatures rise, heirloom tomatoes—open-pollinated varieties grown from seeds that have been passed down for generations—headline backyard plots, farmstands, Michelin-starred kitchens, and beyond. For devotees, the juicy flavors, rainbow colors, and irregular shapes and sizes of heirloom tomatoes are worlds away from the blandly homogenous red armies sold in supermarkets.
But what are heirloom tomatoes, exactly? And how are they different from the ones your nearest grocery chain stocks all year long? Here’s everything you need to know.
What are heirloom tomatoes?
Heirloom tomatoes are flavorful varieties grown from seeds that farmers have saved and handed down from farmer to farmer, usually for at least 50 years. “They’re created by a specific community or culture because they like the traits, the color, or the way the tomato tastes,” Huey says.
To be clear, the tomatoes themselves aren’t antiques. They’re called heirlooms because their seeds predate the grim march of industrial hybridization. In the 20th century, many farmers began crossing tomato varieties to create hybrids that looked uniform, resisted disease, and could withstand long-haul shipping to retailers miles away. Taste was less of a priority.
Meanwhile, “heirloom tomatoes are grown for flavor,” Huey says. Their generations-old seeds are open-pollinated—fertilized by insects, wind, and the like—rather than being manipulated by breeders.
The term heirloom isn’t regulated, though. A savvy marketer can use that word to sell any fruit or vegetable, regardless of whether its seeds were around during the Nixon administration.
Most tomatoes you’ll find in the produce sections of grocery chains are hybrids. They tend to be uniformly red and evenly sized, with thick skins designed to withstand transit.
Heirloom tomatoes are more diverse. Some are the size of cherries or golf balls, while others are charmingly bulgy and weigh up to three pounds. Depending on the variety, they may taste intensely sweet, tangy, smoky, savory, or almost citrusy. Colors include scarlet, orange, green, yellow, blue, deep purple, or a combination; insiders describe the stripey ones as tomatoes with “shoulders.” In any case, expect heirloom tomatoes to have thin skins and juicy, flavorful interiors.
Are heirloom tomatoes genetically modified?
One reason why heirloom tomato varieties vary so much is that they’re not genetically modified. Their generations-old seeds haven’t been altered by human hands eager to sell more produce to far-flung shoppers year-round. Open-pollination preserves the plants’ distinctive family characteristics, so heirloom tomatoes taste like, well, tomatoes.
On the other side of the spectrum lie genetically modified organisms (GMOs). GMOs are engineered for specific traits, such as disease resistance or longer shelf lives.
The first GMO food approved to sell in the U.S. was a hybrid tomato bred to ripen slowly. The product failed “because it did not taste better and was more expensive than other tomatoes,” researchers wrote in a 2000 academic paper. Cue the violins.
Are all heirloom tomatoes organic?
Maybe, but also maybe not. Some heirloom tomatoes are organic, and some organic tomatoes are heirlooms. It all depends on how they were grown.
For any crop to be certified organic, farmers must follow strict guidelines for at least 3 years. There are restrictions on the types and amounts of fertilizers, mulch, and pest control products they use, among other criteria. Some heirloom tomato farmers don’t have the time, capital, or inclination to undergo this process. At the same time, there are certified-organic operations that opt to cultivate hybrid tomatoes rather than heirlooms.
How do you store heirloom tomatoes?
Store underripe heirloom tomatoes at room temperature to preserve their flavors and texture, suggests Layla Schlack, a cookbook editor based in Norwalk, Connecticut. “I find they’re more likely to get mealy if they are refrigerated,” she says, and notes that this can vary depending on the type of tomato.
If you have a surplus of heirlooms and know you won’t be able to eat or cook them before they overripen, don’t fret. Once your heirloom tomatoes reach your desired ripeness, pop them into the fridge to preserve their peak condition. Just make sure to bring them to room temperature before you dig in.
How to use heirloom tomatoes
When heirloom tomatoes are at their peak, they need very little to shine. Tuck thick slices into sandwiches, try a tomato burger, use them to make summer salads, or eat them straight out of hand.
“I’m one of those people who will eat a tomato like an apple and sprinkle salt on every bite,” says Schlack. “When heirloom tomatoes are good, they’re just really good.”
Like a tomato Caesar (hold the lettuce), cheesy tomato hand pies, nuoc cham gazpacho, and more.
