What Is The Difference Between Organic & Heirloom Seeds?

With all of the controversy surrounding GMO seeds, people are seeking out non-GMO options for their gardens.  Organic and heirloom seeds are two such options, but it can be difficult to know exactly what each one means.  I did some research to clarify the distinction.

So, what is the difference between organic and heirloom seeds?  Organic seeds are non-GMO, USDA certified seeds, coming from plants grown with only natural fertilizer, pesticides, and fungicides.  They can be either hybrid or open pollinated.  Heirloom seeds are always open pollinated, and come from plant varieties that are at least 50 years old.  They may also be organic, and they are usually non-GMO.

Of course, this answer may raise even more questions.  For example, what does GMO mean?  What does USDA organic certification mean?  What is the difference between hybrid and open pollinated seeds?  Let’s dig a little deeper to get a little more background on these topics and go into detail on the differences between organic and heirloom seeds.

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What Is The Difference Between Organic And Heirloom Seeds?

To understand the difference between organic and heirloom seeds, we need to know some other terms first.  Let’s talk about what we mean by hybrid and open pollination, GMO, and organic or hybrid seeds.

What Is Open Pollination?

Open pollination means that plants are pollinated by bees, moths, birds, bats, wind, or rain (the plants are “open-pollinated”).

bee on blueberry flower
An open-pollinated plant is pollinated by bees, birds, rain, or wind.

With open pollination, you are allowing plants to breed randomly, with nature taking its course.  Bees or other pollinators visit the flowers of plants and fertilize with whatever pollen they are carrying around.

For more information, check out this article from Wikipedia on open pollination.

What Is A Hybrid Seed?

A hybrid seed is produced by a cross pollinated plant.  Hybrid seeds are specifically bred for improved characteristics, such as higher yield, disease resistance, flavor, or color.

purple bell peppers
Often, the seeds that a gardener buys from seed companies will be hybrid seeds.

To achieve this, a seed grower will deliberately take pollen from a selected plant and use it to fertilize another selected plant.  The idea is to produce seeds that have characteristics of both parent plants.

For more information, check out my article on the advantages and disadvantages of hybrid seeds.

To get a better sense of this, think back to high school biology.  Gregor Mendel noticed that if he crossed two tall pea plants, their offspring (seeds) were more likely to grow to be tall as well.  In the modern day, seed companies can do the same thing to create seeds with the desired characteristics.

For more information, check out this article from Wikipedia on Gregor Mendel and his experiments with pea plants and genetics.

When we talk about hybrid seeds, we may often hear “F1 hybrid” or “F2 hybrid”.  The number after the “F” simply refers to the generation.  So “F1” refers to a first generation seed.  “F2” refers to a seed harvested from an F1 plant (which was grown from an F1 seed).

Remember that with hybrid seeds, you may not be able to grow the same plant again from F2 seeds.  For instance, let’s say you plant an F1 hybrid seed, which successfully grows into a plant.

Then, you harvest the F2 seeds at the end of the growing season.  When you sow those F2 seeds the next year, the plants that grow may not be at all similar to the plant you harvested the seeds from.

This is why gardeners often buy hybrid seeds from seed companies every year.  Of course, one alternative is to cultivate your own heirloom varieties (more on this later).

For more information, check out this article from Wikipedia on hybrid seeds.

What Are GMO Seeds?

GMO stands for “genetically modified organism”.  According to Wikipedia, “a GMO is any organism whose genetic material has been altered using genetic engineering techniques.”

A GMO seed is a seed that comes from a GMO plant (one whose genetic material has been altered).  GMO plants are created in a laboratory for characteristics such as:

  • Increased yield or productivity
  • Improved flavor
  • Longer shelf life
  • Heat or drought resistance
  • Cold resistance
  • Disease resistance
  • Pest resistance
  • Herbicide or pesticide resistance

These traits sound like a good thing for most plants, and it is true that these crops can help to avoid famine and feed more people than we could otherwise.  However, there is some controversy surrounding the question of whether food grown from GMO seeds is safe for human consumption.

For the most part, GMO seeds are used in large-scale, commercial operations for major crops such as corn and soybeans.  For more information, check out this article from Wikipedia on genetically modified crops.

corn stalk
Corn is one crop that is often grown on a large scale with GMO seeds.

Of course, there are ways besides genetic engineering to create plants with desirable characteristics.  For instance, we can breed hybrid varieties or cultivate heirloom varieties over time (more on both of these later).

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What Are Organic Seeds?

“Organic” refers to the way that seeds (and the plants that they come from) are raised.  In order to be certified as organic by the USDA, seeds must be raised according to the USDA’s National Organic Program (NOP) standards.

The NOP is a public-private partnership, and provides accreditation and training to private companies.  These companies then inspect farms and businesses to ensure that they satisfy the standards for organic certification.

These farms and business can then receive the USDA organic seal (you may have seen this on food packaging at the grocery store).  For more information, check out this article from the USDA about organic seals.

According to seedsavers.org, the NOP guidelines say that organic seed growers must plant organic seeds, unless there are none commercially available.  Also, these organic seeds are not exposed to prohibited chemicals (such as certain fertilizers, pesticides, or herbicides) during growth, harvesting, or processing.

Organic fruit is grown from organic seeds, which are not exposed to prohibited chemicals (per the USDA).

For more information, check out this article from Seed Savers on organic seeds and NOP guidelines.

You may also want to check out this article from the USDA on the national organic program.

Organic seeds are never GMO, and they can come from either hybrid or open-pollinated plants.  Since they can be hybrid, they may not “breed true” if you save the seeds and plant them the next year (that is, you won’t get the same variety of plant in the second year that you got in the first year).

What Are Heirloom Seeds?

Heirloom seeds are seeds that come from an heirloom plant.  According to Wikipedia, “An heirloom plant is an old cultivar of a plant used for food that is grown and maintained by gardeners and farmers.”

In practice, this means that a family of farmers or gardeners collects and passes down seeds through generations.  Generally, heirloom seeds come from plant varieties that are at least 50 years old.

pumpkin seeds
Heirloom seeds come from plant varieties that are at least 50 years old.

Heirloom seeds are always open pollinated (see the description of open pollination earlier in the article).  This means that farmers and gardeners are not specifically choosing certain plants to cross pollinate to breed for certain characteristics.

Instead, gardeners and farmers choose the seeds of the most desirable plants every year.  Any resulting changes in plant characteristics happen naturally over time.

Often, these characteristics include improved flavor, increased resistance to pests or diseases, and acclimation to local climate and weather patterns.  Choosing the seeds you want from the plants you want is a modern spin on Darwin’s theory of evolution.

Heirloom seeds are usually not GMO.  However, if an heirloom seed is accidentally open pollinated with a GMO crop, the result could be a GMO seed.  However, this is probably a rare occurrence.

Heirloom seeds are often organic, but this is not guaranteed.  For instance, a gardener using heirloom seeds could conceivably use chemicals in his garden that would disqualify him from USDA organic certification.

So, there can be overlap between organic and heirloom seeds.  In this case, the seeds would be open pollinated (not hybrid), they would come from a plant variety at least 50 years old, and they would be certified organic by the USDA.

For more information, check out this article from Wikipedia on heirloom plants.

Where Can You Find Organic Seeds?

Most seed companies will have the option to buy organic seeds, although they are more expensive than traditional or conventional seeds.  This should be indicated in the print or online catalog for the company.

Johnny’s Selected Seeds, based in Maine, is one company my family has bought seeds from for many years.  For more information, check out the seeds from Johnny’s Selected Seeds.

Where Can You Find Heirloom Seeds?

You can find heirloom seeds at a seed swap or seed exchange.  At these events, farmers and gardeners meet to exchange seeds, including heirloom varieties that have been in the family for over 50 years (some are over 200 years old!)

Heirloom seeds may also be referred to as heritage seeds.  If you are a beginner, you may also be able to learn gardening skills at a seed swap.  For more information, check out this article from Wikipedia on seed swaps.

Seed swaps help to preserve the genetic diversity of plant species.  They also help farmers and gardeners to find new varieties of plants that they can grow and cultivate to their own tastes over time.

Just remember that you cannot save seeds forever – they must eventually be grown, and you can harvest more seeds from the plants for later years. For more information, check out my article on how long seeds last.

If you cultivate your own interesting variety over many years (generations of plants), you can bring the seeds to a swap to trade.  You can even host your own seed swap if you wish.  For more information, check out this article from the Southern Exposure Seed Exchange.

You may also want to check out the Seed Savers Exchange website.


Now you have a better idea of the difference between organic and heirloom seeds.  The distinction can be confusing, but hopefully this article helped to clear things up a bit.

You can learn more about heirloom tomatoes here.

You can find over 30 heirloom tomato varieties of various colors (with descriptions) here.

If you found this article helpful, please share it with someone else who can use the information.

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Jon M

Hi, I'm Jon. Let's solve your gardening problems, spend more time growing, and get the best harvest every year!

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