Seed Saving Basics

Garden Help > Vegetables > Vegetable Gardening Basics

Saving seeds from vegetables and herbs is an easy and economical way to perpetuate favorite varieties.

Top tips for successful seed saving

Save seeds from healthy plants and healthy produce. Seeds from sickly plants may produce weak seedlings, might pass on genetic weakness, or even harbor disease. Choose your best plants to save seed from.
Grow open-pollinated varieties for seed saving. Seeds from hybrid varieties will not 'breed true' and might produce plants very different from the parent.
Know which plants self-pollinate and which cross-pollinate. Seeds from plants that can be easily cross-pollinated by insects or wind may give unexpected results. Learning the scientific family names of your plants may aid in your research.
Let seeds mature on the plant before collecting. For vegetables, this sometimes means leaving them on the plant longer than for harvesting to eat.
Clean and dry seeds, then store in a cool/cold and dry environment.
Label and date seed packets. Include information like plant type, variety, and any special growing conditions such as steps taken to prevent cross-pollination.

Selecting seeds to save

Easy seeds to save

For seeds to breed "true", i.e. look like the parent, successful seed saving requires a little knowledge of how plants are pollinated. Seeds from hybrid (F1) plants may yield unexpected results. The easiest seeds for sure results are self-pollinating plants.

Some examples of easy seeds to save are below. Click on the links for more detailed information on specific plants.

More difficult seeds to save

Saving seeds from plants that can easily cross-pollinate is a little trickier. To produce seed that will give you the same characteristics as your original plant, it is necessary to isolate them from plants of the same species, either by distance or physical barrier. For backyard gardeners, isolation by distance is often impossible, given the distances insects can fly and especially if your neighbors have gardens as well. A physical barrier such as a fine mesh cage or mesh bags on flowers may be needed. If your garden is distant from others, you can also try planting varieties at different times, since the varieties should not cross-pollinate as long as they are not flowering at the same time. See the books listed in the references section for these advanced seed-saving techniques.

Mesh bags can reduce cross-pollination by insects

Broccoli (see section on biennials)
Chives
Cilantro (coriander)
Corn
Cucumber
Garlic
Kale (see section on biennials)
Okra
Onion
Pumpkin
Spinach
Summer squash
Winter squash

Select seeds to collect

Collect from the healthiest fruits on the healthiest plants that have the characteristics you want. Examples: lettuce that bolts last, tomatoes that taste the best, beans that are the most productive.

Collect when the pods or fruits containing the seeds are fully mature. This may be far past the stage at which the vegetable is usually picked to be eaten. Allowing vegetables to reach this stage of maturity can slow down the plant's production. For this reason, you may want to wait to save seeds towards the end of the season, or perhaps grow some plants just for seed saving.

Separate seeds from the plant

There is a dry method and a wet and/or fermentation method to separate and clean the seeds.

Removing beans from pods

Dry method: This method is suitable for dry fruit plants such as beans, peas, lettuce, chives, and most of the broccoli family.

Thresh the seeds to break them out of their hulls or pods and winnow to separate them from any chaff. Some methods for threshing:

Rub the seeds off the plant and out of their hulls.
Pick out the seeds, if they are large and easy to separate.
Put the seeds in a sack and beat or flail them to break them out of their hulls.

To winnow the seeds: carefully toss the seeds in the air in the presence of a light breeze, your own breath, a fan, or a hair dryer on its "cool" setting to blow the lighter plant debris away from the heavier seeds.

Be sure the seeds are thoroughly dry before storing.

Wet method: This method is suitable for fleshy, wet fruit plants such as tomatoes, squash, and cucumbers. In general, the steps are:

Collecting fleshy, wet fruit seeds

Cut open, then scoop or scrape seeds out into a container.
For some wet fruit seeds, especially tomatoes, seeds are fermented before drying. Fermentation removes the gelatinous tissue which has chemicals that prevent the seeds from germinating when they aren't supposed to. Follow the links for detailed procedures for wet fruit plants such as tomatoes, squash, and cucumbers.
If not fermenting, wash in water to remove pulp.
Dry seeds thoroughly inside the house, on a glass, ceramic, or metal surface. Drying seeds on paper towels or cloth is not recommended, as they can stick and be very difficult to remove. Coffee filters can also be used, as seeds do not stick to them. Large seeds, such as squash, can be dried on newspaper.

Store seeds

If insect infestation is a possibility (beans and peas, especially), put the seeds into the freezer in a sealed container for a few days. Be sure seeds are thoroughly dry before freezing. Let the container come to room temperature before opening, to prevent condensation.

Store the clean, dry seeds in the coolest, driest part of the house in a tightly sealed container. Glass jars work well.

Label and date the containers. Include the plant type, variety name, any special notes about the seed source, when the seeds were harvested, and how many plants were harvested. Also include information about any special steps taken to prohibit cross-pollination, especially with seeds from the brassica or cucurbit families.

Consider adding a desiccant, such as a silica gel packet or powdered milk in a porous paper container, to the seed container to absorb moisture.

Seeds of some plants are notoriously short lived, such as onion or carrot. Only plan to keep those for 1–2 years. Others, such as tomatoes and beans can last many years. Seeds that need to be stored long-term or perhaps seeds from a special plant can be stored in the fridge.

References

"Saving Tomato Seeds", UC Master Gardeners of Santa Clara County

"Saving Pepper Seeds", Agricultural Sustainability Institute, University of California, Davis

"How to Save Seeds", Seed Saver Exchange

"The Seed Garden", edited by Lee Buttala and Shanyn Siegel, Seed Savers Exchange, 2015

"Seed to Seed: Seed Saving and Growing Techniques for Vegetable Gardeners, 2nd Edition", Suzanne Ashworth, Chelsea Green Publishing Co., 2002

"The New Seed-Starters Handbook", Nancy Bubel, Rodale Press, 1988

Organic Seed Processing: Threshing, Cleaning, and Storage; M. Colley (Organic Seed Alliance), A. Stone (Oregon State University), L. Brewer (Oregon State University)