Heirlooms, Hybrids, and GMOs – How Are They Different

en It’s the time of year to begin thinking about seeds for your spring/summer garden. Let’s talk about the difference between heirlooms, hybrids, and GMOs.

What is An Heirloom?

An heirloom seed is one with history. An heirloom has been passed down for several generations. Many heirlooms have been passed down for more than a century. An heirloom is anything with enough monetary or other value to be considered worth saving.

With a seed, it’s usually a wide variety of genetic diversity—perhaps that variety is more adaptable to growing conditions or has exceptional flavor or productivity. Heirlooms are open-pollinated—meaning they are pollinated through natural methods (wind, bees, butterflies) and will breed true to their parents.

Many gardeners believe that the finest flavors come from heirlooms. Heirloom tomatoes, like Brandywine, German Johnson, Cherokee Purple, Mortgage Lifter, etc., are consistent winners at flavor trials.


A hybrid occurs when two different plants are bred to produce an offspring that has one or more qualities of the parent plants. For example, a farmer grows a variety of squash with excellent flavor but perhaps doesn’t produce many squash. He grows another squash that is very prolific but rather ordinary in flavor. Then he pollinates the flowers from the one with excellent flavor with pollen from the prolific one. He continues to do that, selecting the plants with his desired qualities. After a generation or two (or more), he winds up with a squash with exceptional flavor and productivity.

Hybrids can offer some disease resistance and vigor that the original variety didn’t have. The downside is that the seeds do not breed true—instead, they revert to one of their parents.  The companies that hold their patents control their production—and their price. That is of particular concern if you are a farmer.


While hybrids can naturally occur in nature or be easily done by man, GMOs are created using high-tech methods that alter a plant’s DNA in a way that could not occur naturally. They may involve gene-splicing or even inserting genetic matter from a non-related species—hence the infamous Bt corn—which has inserted a non-related toxin that kills corn earworms.

My garden is a mix of both heirlooms and hybrids. One of my favorite two tomatoes is a slicer called Cherokee Purple. The other is a hybrid cherry tomato called Sun Gold (or a sister variety called Sun Sugar). I usually tuck in a Better Boy, a hybrid, because of its disease resistance and grow another undetermined heirloom (to try a new variety).

By the way, GMO seeds are, at this time, not allowed to be sold to a home gardener, only commercial growers.


The Great Big Greenhouse will have a great selection of Heirloom and Hybrid seeds. Stop in and pick some up today.

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