Tomato Tomtahto

Let's talk tomatoes! You may have noticed that there are two kinds of tomatoes in the bags this year: a regular firm, round, red, modern hybrid variety, and an heirloom-type that's dark, soft, oddly shaped, and very tasty. Although both are tomatoes just the same, we farmers and food writers somehow always talk about hybrid tomatoes vs heirloom tomatoes, with heirlooms definitely the gold standard in the tomato world. But what exactly is it to be an heirloom tomato?

The "social" definition of an heirloom tomato is one with a story: an open-pollinated variety cultivated year after year by careful seed saving which, because of superior quality, was kept in a family or achieved a measure of local or regional fame. Many heirloom types are from other parts of the world--cherished varieties that can be specifically tied to a group of people and were brought to America by early immigrants. The preservation of these seeds was not due to sentimentality, but because these were time-tested varieties bearing an implicit seal of approval. Heirlooms represent, quite literally, the interwoven fabric of both natural and human history.

But many backyard hobbyists and commercial breeders still create new open-pollinated varieties with standout "heirloom tomato" qualities even today. In fact, this year I'm growing out some seeds I saved from two fruits of unknown cross that turned up in the field a couple years ago. These new "heirloom" tomatoes have none of the lineage or history, but have all of the characteristic exciting stripes, colors, irregular shapes, and strong flavors we associate with other soft, thin-skinned "heirlooms." All these modern tomatoes meet the "aesthetic" definition for "heirloom tomatoes"--and yet, some of the historically kept heirloom varieties from 100 years ago or more were, in fact, plain red tomatoes, entirely uninteresting and which would never pass as heirlooms today on any restaurant menu or farmers market table.

Moreover, as much as the dark, soft, tasty tomatoes in your bags meet this definition of "heirloom tomato," they do not, in fact, meet the "scientific" definition--and, surely, science should be the one to settle all this confusion, right? Botanically, an heirloom tomato is simply any open-pollinated variety, as opposed to a hybrid variety of tomato. That is, pollinating the flower with pollen from the same tomato variety makes fruit containing seeds that will reproduce the tomato, true to type. Growers can save seed from their crop and sow again in following years. A hybrid variety, however, is grown from seeds produced by mating two open-pollinated varieties together.

And truth be told, the "heirloom" tomatoes in your bags today are in fact hybrid tomatoes produced by crossing two different heirloom tomatoes together. Scientifically, the heirloom tomatoes in your bags are just plain-ol' hybrids...but seeing them as heirlooms may offer a more useful understanding of culinary reality.

Some tomatoes are easily categorized, such as a hard red shipping hybrid from the grocery store or Radiator Charlie's storied heirloom Mortgage Lifter, but the more ambiguous the tomato, the more it pushes the boundaries of its label, the less these seemingly-intrinsic scientific categories help us understand the world.

And that might sound subjective and un-scientific but in fact, this is exactly how biological categories are applied even in biology itself. In conversation with a botanist friend once, I tried to pin down with them the essential features that scientists use to distinguish one plant species from another, and was quite disappointed to find my layman's understanding of science to be incorrect: plants are out there doing their plant thing, and nothing differentiates one species from another but scientists themselves, making up labels in their effort to describe and understand the world. Boundaries are ill defined, and, to my great consternation, the very same plant growing in two separate parts of the country may be called a different species, although they are otherwise identical!

In many scientific disciplines there is big debate between opposing factions of "Lumpers" and "Splitters" about how labels are best utilized; the lumpers feeling like putting similar-enough things together under the same label describes their world well, and the splitters feeling that slicing & dicing to fine-grained labels allows for better understanding.

This imperfect human interplay may be the real reason this whole idea of "what is an heirloom tomato" is so complicated in the first place--leaving us with, in the end, no "real" answer at all. All I can do, at this point, is to come down on the side of the lumpers for the weekly vegetable list and simply call them all "tomatoes."