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Saving, storing and treating vegetable seeds

A person in a white shirt, blue jeans with a yellow button up holding two tomatoes, one larger than the other. Both are a cherry orange color.
When saving tomato seeds, look for unblemished fruits from healthy, disease-free plants.

The gardening season is coming to a close. If you are saving seeds, now is the time to start collecting them.

Choosing which seeds to save

Some vegetables are self-pollinating, while others are not.

Self-pollinating vegetables are more likely to produce what you'd expect, they include tomatoes, peppers, beans and peas.

Cross-pollinating vegetables are more likely to cross with other varieties in your garden or your neighbors’ gardens, leaving you with a less predictable outcome. Vine crops have separate male and female flowers, which can cross-pollinate. Avoid saving these seeds if you have multiple different vine crops in your garden, as you can end up with a zucchini-pumpkin hybrid that doesn’t have the best qualities of either parent.

The variety of your plant also makes a difference in seed-saving success. If you planted an heirloom or open-pollinated variety, it is a good candidate for seed saving. If you planted a hybrid variety, saving seeds will result in plants that don’t necessarily have the good qualities of the parent.

It is also important to save seeds from healthy plants. Look for plants free of disease symptoms, and unblemished fruit or pods.

Storing seeds

The best time to harvest seeds can depend on the vegetable. See Saving vegetable seeds for recommendations on when to harvest.

In general, store your seeds in a cool, dry, dark place over the winter, and try to use them in the next couple of years. The longer seeds are stored, the less likely they are to germinate well. 

Treating seeds

If you’ve been disappointed by seedborne diseases when saving your own seeds, hot water seed treatment is one way you can reduce the chance of diseases showing up next year. This process needs to be performed very carefully, as it can kill seeds if directions aren’t followed to the letter.

Treating seeds is especially important to reduce the risk of transporting diseases from garden to garden if you are sharing seeds with others or using seeds from a seed library. 

Some people treat them right after harvesting them. Others prefer to do this in the winter when they have some downtime. And others prefer to do it right before planting in the spring.

As long as you follow the instructions carefully, hot water treatment at any time should not impact germination.

The Ohio State University has good videos and fact sheets about how to hot-water-treat your seeds.

Authors: Marissa Schuh and Natalie Hoidal, Extension educators

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