Chris Izworski

Heirloom vs. Hybrid Seeds: What’s the Difference?

Open-pollinated, heirloom, hybrid, GMO — what the labels mean and why it matters

Walk into any garden center in March and you’ll see seed packets labeled “heirloom,” “hybrid,” “open-pollinated,” and occasionally “non-GMO.” These terms get thrown around casually, but they mean specific things — and understanding the differences changes how you think about your garden.

Open-Pollinated: The Baseline

Open-pollinated simply means that if you let a plant pollinate naturally — by wind, insects, or self-pollination — and save the seeds, the next generation will be essentially the same as the parent. The genetics are stabilized. What you grow is what you get.

All heirloom seeds are open-pollinated, but not all open-pollinated seeds are heirlooms. A plant breeder can develop a new open-pollinated variety through years of selective breeding, and it won’t be an heirloom until it’s been around for a while.

Heirloom: Open-Pollinated With History

An heirloom variety is an open-pollinated cultivar that has been maintained and passed down over many years — typically at least fifty, though there’s no official cutoff. Brandywine tomatoes, Scarlet Runner beans, Bloomsdale Long Standing spinach — these are varieties that gardeners have been saving and sharing for generations.

Heirlooms exist because someone thought they were worth keeping. Maybe the flavor was exceptional. Maybe they grew well in a particular region. Maybe they held cultural significance for a family or community. Each heirloom variety carries a story, even if the story has been partially lost to time.

The practical advantage of heirlooms is seed saving. Because they breed true, you can save seeds from this year’s Brandywine and plant them next year with confidence. Over time, your saved seeds even adapt slightly to your specific conditions — your soil, your microclimate, your pest pressure.

Hybrid (F1): Engineered Vigor

A hybrid — typically labeled F1 — is the first-generation cross between two distinct inbred parent lines. The plant breeder maintains those parent lines separately and crosses them each year to produce the hybrid seed.

Hybrids exist because of a phenomenon called heterosis, or hybrid vigor. The first-generation cross often produces plants that are more vigorous, more uniform, and higher-yielding than either parent. This is real biology, and it’s why hybrid tomatoes often outperform heirlooms in commercial yield trials.

The trade-off is that hybrid seeds don’t breed true. Plant the seeds from an F1 hybrid and the second generation (F2) will be a chaotic mix of traits from both parent lines — some good, some bad, all unpredictable. You can’t save seeds from hybrids and expect the same plant next year. You have to buy new seed each season.

This isn’t a conspiracy. It’s genetics. But it does mean that hybrid varieties keep you dependent on the seed company in a way that heirlooms don’t.

GMO: A Different Conversation Entirely

Genetically modified organisms — GMOs — are plants whose DNA has been directly edited in a laboratory, usually to insert a gene from a different species. Bt corn, for instance, contains a gene from a soil bacterium that makes the plant toxic to certain caterpillars.

This is fundamentally different from hybridization, which works within the normal boundaries of sexual reproduction. Hybridization crosses two tomato varieties. Genetic modification might insert a gene from a completely unrelated organism.

For home gardeners, GMOs are largely irrelevant. GMO seeds are not available to consumers — they’re sold exclusively to commercial farms through licensing agreements. Every seed you buy at a garden center or from a seed catalog is non-GMO, regardless of whether the packet says so. The “non-GMO” label on home garden seeds is technically accurate but functionally meaningless — it’s marketing, not information.

So What Should You Plant?

It depends on what you value. If you want to save seeds, grow heirlooms and open-pollinated varieties. If you want maximum yield and disease resistance and don’t care about seed saving, hybrids are often the better choice. Most gardens benefit from a mix of both.

I grow mostly heirlooms at Freighter View Farms because seed saving is central to how I garden. But I’m not dogmatic about it. Some hybrid varieties are genuinely superior for specific purposes — certain disease-resistant tomatoes, for example, or hybrid sweet corn that ripens more uniformly. The goal is to make informed choices, not to pick a side.

The more important thing is to read the label. Know what you’re planting. If the packet says F1 or hybrid, enjoy the plant but don’t bother saving its seeds. If it says open-pollinated or heirloom, you have the option — and once you start saving seeds, you may find it hard to stop.

At Freighter View Farms, I grow and document heirloom varieties adapted to Michigan’s Zone 6a — tracking what thrives on the shore of Saginaw Bay and sharing the results. If you’re interested in the intersection of traditional growing practices and modern food systems, I write about it on Medium and LinkedIn.

Chris Izworski

Writer, gardener, and technologist in Bay City, Michigan. Writes about AI, Great Lakes living, and what it means to pay attention.