There are three general ways to process seeds you are planning on saving, and some seeds that are easier to harvest and save than others. For a list of instructions on saving seeds from a variety of common garden plants, click here.
Methods for Processing and Saving Seeds
Dry Seed Processing
For plants with seeds that grow on the outside of the plant:
- Allow the seed to dry on the plant and collect seedpods before they break open.
For plants with seeds that develop in the center of the flower:
- Allow the plant to dry.
- When the stem holding the seed head turns brown, harvest the seeds.
Tip: Collect dry seeds under dry, warm conditions to prevent mold and reduce drying time.
Wet Seed Processing
For seeds that grown inside the fleshy fruit of the plant:
- Rinse off the seeds and dry them thoroughly.
Tip: If the seeds have a gel-like coating, use the fermentation process.
Fermentation Seed Processing
For seeds with a gel-like coating:
- Mix the seeds and the seed juice with a little water in a small plastic or glass container with a lid.
- Allow the seeds to ferment for 4-6 days.
- When a layer of mold has formed on top of the water and the seeds sink, the fermentation is complete. Add more water, swish it around and remove the mold and pulp. The good seeds will sink to the bottom and the bad seeds will float to the top. Remove the bad seeds.
- Drain the water from the seeds and set them out on a plate, screen or paper towel to dry thoroughly.
Tip: Use the fermentation process for tomatoes, cucumbers, some squash and some melons.
For All Seeds
- Once seeds are completely dry, place them in a moisture-proof container. Label and store seeds in a cool, dry place.
- If possible, return a few seeds to the Concord Seed Lending Library at the Fowler Branch Library in one of the seed return envelopes provided.
- If you are interested in swapping seeds with others, we have a list available at the Fowler Branch Library of other patrons who are interested in seed swapping. We would be happy to connect you.
- We also expect to have a seed saving kit available as part of the Library of Things soon - stay tuned!
A Guide to Seed Saving Difficulty
Seeds require different levels of work, experience and space to properly save. If you are new to seed saving, we recommend starting with beans, lettuce, peas, or tomatoes. These seeds are called “selfers” because they are self-pollinating. This means that the seeds you save from them will reliably produce plants like the original one planted because it pollinated itself.
Tip: Stick with one variety of a plant, or separate different varieties with a taller buffer crop or distance.
Other seeds are more likely to cross-pollinate with different varieties of the same plant that are growing nearby. It requires special planning to make sure that the seeds you save will grow into the original variety and not a hybrid variety. Seeds that are insect pollinated or biennial fall into this category. These seeds are likely to cross-pollinate with other varieties of the same plant to grow a hybrid plant. They may also take more than one season to produce seeds.These include beets, carrots, chard, and parsley, parsnips, and peppers.
Tip: Choose only one variety from each plant or separate similar plants by placing them a good distance apart, like in the front and back yard.
Difficult seeds grow plants that are wind or insect pollinated and very likely to cross-pollinate with other plant varieties. These include broccoli, cabbage, cauliflower, corn, cucumbers, melons, pumpkins, and squash.
Tip: Stick to the single plant variety, stagger growing times, and use tenting or hand pollination techniques to preserve the purity of the seed. It’s also important to check the botanical name to determine which plants are related and susceptible to cross-pollination.