Heirloom, Heritage, Hybrid, Open-pollinated?

One of my pet projects is collecting Australian heritage vegetable varieties. I was delighted to find that there were quite a few more than I had expected. One of the things I’ve found in this area is confusion over terminology, so I thought I’d just clarify is it Heirloom, Heritage, Hybrid, Open-pollinated? For those interested.

Open-pollinated

I’ll work backwards and get the last term out of the way first. An open-pollinated plant is one which is pollinated naturally, without human intervention. Provided that no unwanted cross-pollination occurs, the plant should breed true. In other words, its offspring should resemble the parent(s), or it least resemble the general type. For example, the tomato College Challenger should produce offspring which exhibit similar characteristics to the parent: an indeterminate, regular leaf plant producing good quantities of medium-sized, tasty, red beefsteaks beginning production mid-season.

If cross-pollination by another variety within the same species, or by another species altogether occurs, the offspring is a hybrid. Strictly speaking, it is an F1 hybrid, where F1 means first filial generation. Cross-pollination can occur naturally or intentionally, so hybrids occur in nature as well as in plant breeding labs.

Hybrid

A hybrid, whether deliberate or not, can become open-pollinated through a process of growing, collecting seed, growing and so on over successive generations, sometimes taking many years. This is called dehybridization. All it requires is space, time and patience. The books 100 Heirloom Tomatoes for the American Garden (ISBN: 0761114009) and Breed Your Own Vegetable Varieties (ISBN: 0316181048) are excellent places to start if you’re interested in this area. A heritage variety, or even plant for that matter, is one that has some significance to a particular region or culture. In this group, I would include all older commercial varieties as well as those that could be classed as heirlooms (see below). For example, the lettuce variety Gold Rush is an Australian heritage variety of particular significance to the Ballarat region in Victoria from whence it comes. Similarly, the tomato Paragon is an American heritage variety, being an 1870 commercial release from the Livingston Seed Company, founded in 1850 by Alexander Livingston.

Heirloom & Heritage

At last we come to heirloom, a much used term. I will define it as a variety that has been passed from generation to generation within a family or community. An example of an heirloom would be the bean Lohrey’s Special, grown by the Lohrey family of Tasmania for generations.

Clearly, an heirloom is a heritage variety, but not all heritage varieties are heirlooms, at least not by my definition. Are they necessarily open-pollinated? The answer is, surprisingly, no. Most vegetables are propagated from seed. For these, it is challenging to imagine there being any hybrid heirloom or heritage varieties. Some vegetables though are propagated vegetatively. That is, they are cloned. The potato is the classic example of cloning over successive generations. When a new potato variety pops up, it is more often than not the result of sexual reproduction. In other words, a group of potato plants is left to flower and go to seed. These seeds, not seed potatoes but true seeds, are then grown. If one of these plants produces good spuds, a new variety is born. The only way to maintain it is by growing from tuber year after year. As these true seeds were more than likely the result of cross pollination, that first plant would have been a hybrid, and so would all subsequent plants grown from saved tubers.

So there we have it. The terms heirloom and heritage give a plant or plant variety a social, i.e., human context. The terms open-pollinated and hybrid just refer to the origin of the pollen that does the fertilising. Heirloom varieties make up part of the larger group of heritage varieties. They can be open-pollinated or hybrid.

In summary:

• Not all heritage varieties are heirlooms, but all heirlooms are heritage varieties.
• Heirlooms have a social, human context.
• Open-pollinated and hybrid refer to the origin.