What Are Heirloom Seeds?

Heirloom seeds are curated over many generations for their ability to produce plants of characteristic beauty and culinary superiority. The names of some heirloom plants can be just as colorful as the blooms: Radiator Charlie's Mortgage Lifter and Cosmic Eclipse tomatoes, Viola “Bunny Ears”, and Pippin's Golden Honey Pepper, to name a few. Some heirlooms have been around for centuries, crossed oceans, won blue ribbons, and came close to extinction only to be saved by a lone volunteer sprout the next year. That’s the beauty of these seeds: Gardeners can continuously save and grow them, adding a new chapter to a plant's legacy.

The Difference Between Heirloom, Hybrid, and Genetically Modified Plants

New gardeners may wonder how heirloom seeds are different than hybrid seeds, and where genetic modification comes into the picture.

Heirloom Seeds

Heirlooms produce viable, true-to-type seeds through open pollination, or pollination via by wind, bugs, or birds, which leads seeds to produce a plant just like the parent plants. To make sure seeds produce true breeds, breeders isolate them from similar varietals.

Heirloom seeds predate 1945 and the post-war rise in hybrid seeds sold to farmers and gardeners. Before that time, the USDA trained growers to breed and save their own seeds. This is considered an ancient practice; farmers have always selected plants with desirable traits to maintain, generation after generation. Indigenous people in the Andes, for example, have grown thousands of specialized types of potatoes, while Anasazi and Hopi people of the southwest cultivated the best beans for their land and cuisine, and some of these are still available.

Hybrid Seeds

While hybridization can add to genetic diversity, hybrid seeds sold for farm or garden use come from controlled cross-pollination. Breeders combine plants with different characteristics, and the resulting plant presents the dominant traits of each parent. Many are labeled “F1”, which means first filial generation, or the offspring of two non-hybrid plants. A loganberry, for instance, is considered a blackberry-raspberry hybrid, while an olallieberry is a hybrid of a loganberry and a youngberry.

Commercial hybrid seed companies aim to address the challenges of productivity, hardiness, drought tolerance, pests and pathogens, shelf life and transportability, homogeneity, and customer expectations. Reliable, resistant seeds can keep farmers in business and new gardeners enthusiastic.

Genetically Modified Organisms (GMO) and Seeds

The World Health Organization determined that genetically modified foods are derived from organisms whose genetic material has been modified in a way that does not occur naturally. Many of these foods were developed to improve resistance to plant diseases or to increase tolerance of herbicides. Most genetically modified seeds are commodity crops, such as cotton, corn, or wheat. Environmentalists like the Canadian Biotechnology Action Network or the Pesticide Action Network have voiced concern about the effects of genetically modified plants, especially those bred for insect resistance, on insects and non-genetically modified plants and soil. 

Both organic and heirloom seeds are specifically non-GMO. Only some hybrid seeds are labeled non-GMO, and the F1 status refers to normal hybridization and not gene splicing.

The Benefits of Planting Heirloom Seeds

The practice of growing and saving heirloom seeds provides ample rewards to farmers as well as farmer's market customers.

Taste and Enjoyment

For the home gardener or specialty crop farmer, bold flavor and singular beauty are reason enough to save heirloom seeds. For example, as opposed to commercial tomatoes, heirloom tomato are perfectly acidic, sweet, or mellow for your taste buds. For a seller, many farmers’ market customers appreciate the variety and are drawn to the distinctive specialties that set a vendor apart.

Self-Sufficiency and Location-Specific Development

For many growers, the ability to save the seeds of a wildly successful heirloom flower or vegetable is accompanied by a sense of independence from the large corporations. In addition, these seeds acclimate to the farmer's specific growing conditions and develop resistance to local pests and diseases. Consider it evolution on a small scale.

Genetic Diversity and Seed Saving

A study published in 1990 found that about 93% of seed varieties sold in the U.S. in 1903 were extinct by 1983. Commercial seed catalogues in 1903 offered 497 varieties of lettuce, and, in 1983, only 36 of those varieties remained. By planting heirloom seeds, anyone can join a community of growers, gardeners, chefs, Indigenous seed savers, seed banks, and seed-swappers who are revitalizing the diversity of our gardens and our food system.