GMO, Organic, Hybrid and Heirloom seeds. What does it all mean?

There are so many terms out there when it comes to seeds, but do you know what each of them really means?





GMOs, or “genetically modified organisms,” are plants or animals created through the gene splicing techniques of biotechnology (also called genetic engineering, or GE). This experimental technology merges DNA from different species, creating unstable combinations of plant, animal, bacterial and viral genes that cannot occur in nature or in traditional crossbreeding. Think of taking the gene from a cat and inserting it into a gene from a human.  You can see why they have received the nickname of “Frankenfoods”

Currently commercialized GM crops in the U.S. include soy (94%), cotton (90%), canola (90%), sugar beets (95%), corn (88%), Hawaiian papaya (more than 50%), zucchini and yellow squash (over 24,000 acres). (Number in parentheses represents the estimated percent that is genetically modified.) These varieties are generally only available to commercial farmers.  Blue corn cross-pollinates with current GM corn varieties. And now, with the sugar beet growers going GM, there is the possibility of cross-pollination into other beet varieties and near relatives, such as chard. All but soy cross-pollinates.

It is unlikely that other seed varieties, whether organic or not are GM, though contamination may occur by cross pollination or other means from experiment and sometimes publicly undisclosed GM test plots throughout the nation.


Certified Organic seeds are seeds that have been harvested from certified organic plants.  That is, without the use of synthetic fertilizers, pesticides, antibiotics, food additives and irradiation. Organic seeds can be heirloom and/or hybrid, but are never genetically modified.

It is interesting to note that an organic producer may use non-organically produced, untreated seeds and planting stock to produce an organic crop if there is no organic seed variety commercially available.




A hybrid seed has been cross-bred with another variety to try and enhance its results. For example, one might try and cross breed it with another variety that has disease resistance. Think of cross breeding a Labrador with a Poodle! The problem with hybrid seeds is that when a gardener tries to save the seeds from that variety it typically reverts back to its wild parent and will never really know what will grow.


Heirloom seeds have typically been grown for generations, often 50 years or more.  However there is no specific longevity requirement for a seed to be classified as an heirloom.


Open-Pollinated is when pollination occurs by insect, bird, wind, humans, or other natural mechanisms. Because there are no restrictions on the flow of pollen between individuals, open-pollinated plants are more genetically diverse. This can cause a greater amount of variation within plant populations, which allows plants to slowly adapt to local growing conditions and climate year-to-year. As long as pollen is not shared between different varieties within the same species, then the seed produced will remain true-to-type year after year



What’s the Difference Between Genetically Modified, Heirloom, Hybrid, Non-Hybrid, and Open Pollinated Seeds?

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