Trait 1: Age

Some authorities say that heirloom vegetables are those introduced before 1951, when modern plant breeders introduced the first hybrids developed from inbred lines. Some heirlooms are old European crops, some of which have been in cultivation for almost four hundred years. Still other heirlooms trace their ancestries to Africa and Asia.

Just as different gardeners have different ideas about how old heirlooms are, they also have different ideas about which old varieties are heirlooms. To some, nearly all the old-time varieties are heirlooms. To others, varieties can be old without being heirlooms. They exclude, for example, commercial varieties and those that appeared in the seed trade, limiting heirlooms to those local or regional varieties that were passed down from generation to generation of gardeners.

While I can appreciate the reasoning of those that view heirlooms as a narrow subset of all old varieties, I side with those who include nearly all the old-time varieties with the heirlooms. For starters, many of the old varieties that went on to fame and fortune as commercial successes started small. Take the ‘Hubbard’ squash, for example. There really was a Mrs. Hubbard who found this variety, which was later popularized by seedsman James J. H. Gregory.

I also consider old varieties to be heirlooms because so many of them are threatened with extinction. Should we neglect to save such varieties just because, at one time or another, they were popular enough to be commercial successes?

Trait 2: Open-Pollinated (OP)

When heirloom gardeners refer to open-pollination, they mean that a particular cultivar can be grown from seed and will come back “true to type.” In other words, the next generation will look just like its parent.

Now, however, there are more and more vegetables that will not come back “true to type.” For example, plant nearly any F-1 hybrid tomato, and save some seeds from the crop. Next spring, plant them, and see what happens. The seed may not even germinate, since it may be sterile. If it does sprout, the young plants will probably not have many of the characteristics that made its parent noteworthy. While hybrids have many outstanding qualities, the ability to reproduce themselves is clearly not one of them.

Heirloom gardeners are, of course, aware that the term “open- pollination” is a bit of a misnomer, because there is nothing at all open about the pollination of many heirloom vegetables. Take squash and pumpkins, for example. They cannot be left to pollinate each other willy-nilly, or the resulting offspring will be mongrels. While some may be interesting, the original type will be lost. Like the squash family, the brassicas (cabbage, cauliflower, broccoli, and their kin) also cross readily, as do several other vegetables. Gardeners who hope to save seed of such vegetables have to isolate either the plants or their flowers to prevent such unwanted crossings.

Another problem with the term “open-pollination” is that some of these crops are not even grown from seed, and no pollination, open or otherwise, is required to keep these varieties going. Finally, that open-pollinated varieties can come back true to type does not guarantee that they always will. Gardeners in the past knew that open-pollinated seed would occasionally produce an off-type seedling. To maintain a seed line, they looked for and removed off-type seedlings.

Trait 3: Quality

What draws many gardeners to heirlooms is flavor. They want a tomato that tastes like a real tomato, not a plastic one. After trying varieties that look good on the pages of seed catalogs but just don’t taste like much, they turn to heirlooms.

What they find may well be something of a mixed bag. The best of the heirlooms really are wonderful. They have it all. They taste wonderful, look beautiful, and are easy to grow. There are, however, varieties that take a more experienced hand to grow well. Some are local or regional varieties that may or may not be suited to conditions in your own garden. Others are susceptible to problems unknown to earlier gardeners. Today new, resistant cultivars may be the only ones suited to areas where certain diseases and pests are entrenched.

Finally, heirlooms can be quirky. Seeds may germinate slower than their modern counterparts. As they grow, some heirlooms have traits that are downright strange. For example, I once grew an heirloom cabbage variety that seemed to tip its crown upside down until it had six or so true leaves. Then it turned right-side up and grew just fine.

All gardeners can do is wait to see what happens, perhaps reflecting on all the things our gardening forebears knew and the wonders of biodiversity.