A Seed Primer: What’s the Difference Between Open Pollinated, Heirloom, and Hybrid Seeds

seed catalogs with open pollinated, heirloom, and hybrid seeds

It’s the most wonderful time of the year: when seed catalogs arrive in the mail!

Seed catalogs mark the transition between the end of the autumn growing season and the beginning of winter planning.  And if planning doesn’t sound enticing to you, just imagine this: a cold winter day, a hot cup of tea, a cozy blanket, and a stack of colorful seed catalogs.

Gosh, I just can’t wait!  And luckily, I don’t have to, because the first two have already arrived.

Before you jump into your seed catalogs, here’s a quick primer on seed classification. During my 4 winters in sales at High Mowing Organic Seeds, the most common questions I got were:

“Are hybrid seeds GMO?”

“What’s the difference between heirloom and open-pollinated?”

“Can hybrid seeds be organic?”

And so on…

So, before you open those seed catalogs, here’s a primer on open pollinated, heirloom, and hybrid seeds:

Open Pollinated (OP)

seed startingOpen pollinated seeds refer to seeds that are pollinated by wind or insects and are “true to type.”  This means that the next generation of seeds will produce a variety identical to the one you planted.

When you’re growing OPs for seed, you need to isolate them or stagger their planting and bloom time so they won’t cross-pollinate with another variety of the same crop.  If they did, you’d end up with an unintentional hybrid.



Heirloom seeds are old varieties passed down from one generation to the next.  All heirloom seeds are open pollinated.

They often carry a story with them, are closely tied to a specific region where that crop or variety grew well, and are prized for flavor.  Heirloom seeds tend to conjure up images of immigrants leaving their homelands and bringing seeds with them to plant in their new country, which is how many heirlooms made it to North America from Europe.

Today, we typically think of heirlooms as varieties that pre-date modern breeding work, which began at land-grant Universities in the 1920s and 30s.

Newer OP varieties will eventually become heirlooms.  One example is “Green Zebra” tomato, which is often mistaken for an heirloom because of its unusual appearance and tangy, delicious flavor.

*This is a good place to note that if you’re growing for taste above all else, don’t shrug off OPs or Hybrids.  While it’s true that supermarket vegetables are bred for holding up during transport, there are tons of modern varieties that are bred for flavor first.


Hybrid seeds are the result of two OP varieties being intentionally cross-pollinated.  The key word here is intentionally.  Cross pollination happens all the time in nature, with the help of wind and insects.

In the seed production world, hybrids are created by planting two varieties of the same crop next to each other, and then cross-pollinating them by hand.

Hybrids are always indicated by “F1” which means filial 1, or first children.  You can think of it as two parent plants having sex (because that’s what pollination is in the plant world), and creating a child: the new variety.

[You can create a hybrid in your own garden.  High Mowing Organic Seeds sells a kit for you to grow out one of their most popular hybrid zucchinis, Cha-Ching F1.]

Hybrids are known for increased pest and disease resistance and higher yields.  While OPs can also have these characteristics, creating a hybrid can get you there faster than selectively breeding for OPs.

However, hybrids will not produce seed true to type.  Instead, the seed saved from a hybrid will revert to characteristics of the two parent plants, and each seed may produce a different looking/tasting variety.  If your primary goal is to save seeds, stick with OPs.

planting organic seeds

One last important thing about hybrids: hybrids are not GMOs.  

GMOs, or genetically modified organisms, are created in labs by using viruses and bacteria to invade cells in order to introduce foreign genes into those cells.  This means crops that could not cross-pollinate in nature can be fused together in the lab.

It also means that pesticides can be inserted into the gene structure of a plant, which is the case with much of the GMO corn.  And that means you can’t wash the pesticide off.

There are hundreds of seed companies that have signed the Safe Seed Pledge, pledging to not sell GMO seeds.  

You can find a comprehensive list of these seed companies on the Council for Responsible Genetics website.

Okay, you’re ready!  Time to pour your tea and dive into those seed catalogs!

Tell me, where’s your favorite place to buy seeds?  Do you save your own seeds?  Are you as excited for seed catalogs as I am? 🙂 Let me know in the comments below

3 thoughts on “A Seed Primer: What’s the Difference Between Open Pollinated, Heirloom, and Hybrid Seeds”

  1. Pingback: Organic vs. Conventional: Why You Need to Buy Organic Seeds - The Good Heart Life

    1. We love High Mowing Organic Seeds, an all organic seed company in VT. We also use Johnny’s Selected Seeds, based in Maine, and Fruition Seeds in NY. Happy growing!

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