Heirloom seeds are the seeds of purebred plants, uncrossed or uncontaminated by other seed varieties. Storing heirloom seeds for continued use is not especially difficult. First you need to know how to collect and dry the seeds appropriately. Once the seeds are dry, they must be kept in dry, cool conditions.
Vegetables with Seeds in the Flesh
1Pick vegetables that are overripe. Plants with under ripe or ripe vegetables will not have gone to seed yet. A vegetable needs to completely finish a developmental cycle before the seeds are fully mature. As a result, you should wait until the vegetables are brown and overripe.
2Scoop the inside out. Cut the vegetable open with a sharp, clean knife and scoop the pulpy, seed-filled flesh into a bucket.
- Note that for tomatoes, you can throw the entire vegetable into a bucket instead of scooping out the inside.
3Add water to the bucket and let the flesh sit. After several days, it will begin to rot. As the flesh rots, the seeds will separate and rise to the surface of the water. Viable seeds, on the other hand, will sink to the bottom.
4Change the water after the seeds separate. Pour the water through a find mesh sieve, performing the action carefully to prevent the loss of seeds. Rinse the seeds by pouring new water into the bucket or by running them under water in a fine sieve.
5Dry the clean seeds. Spread the rinsed seeds out on newspaper or clean paper towels. Let them sit in a room temperature location for several days until completely dry. Move them around periodically to prevent the seeds from germinating, however.
Vegetables with Seedpods or Dry Seeds
1Allow the plants to come to seed. Do not deadhead or remove flowers, and do not harvest vegetables upon ripening. Instead, let the flowers die off naturally and let the vegetables become overripe. Approximately six weeks after you would normally harvest your vegetables, seedpods should have developed and matured.
2Allow seedpods to dry on the plant. For vegetables, the pods will usually turn yellow or brown during this time. Corn seedpods shrivel and develop a hardened exterior. For flowers, the blooms will lose their petals and the stems will turn brown.
3Harvest the seedpods or seed heads. Pluck them off the plant using your fingers or gently snip them off using clean scissors or shears.
4All the pods to dry. Lay them out on newspaper and place them in a dry, warm location. Allow the pods to dry for one to two weeks.
5Shell the pods. After the pods have become dry, carefully peels the crumpled shell protecting the interior seeds. For flowers, you will need to crumble the flower heads to obtain the seeds.
Preserving the Seeds
1Save plenty of seeds. As a general rule, you should save seeds for as many plants as possible to produce an adequate harvest the following year. Self-pollinating plants, like beans and tomatoes, do not need an excessively large number of seeds, and the same goes for plants that are both self-pollinating and cross-pollinating. Plants that rely on cross-pollinating, though, need large amounts of seed.
2Dry seeds further using silica gel. If you plan on storing your heirloom seeds for more than one season, you should consider drying them out even more than usual. Place the seeds in a glass jar filled with an equal weight of dry silica gel for one week.
3Transfer the dried seeds to an airtight container. A freezer-safe storage jar or plastic sandwich bag should work. Keep each seed type in its own separate container. Do not mix the seeds since mixing increases your odds of cross-pollination between varieties.
4Sprinkle the inside of the containers with diatomaceous earth. This organic product is an effective way to kill off any insect or pest eggs that may be hiding in the midst of your seeds. Add just a little DE to the container and mix the seeds around to spread it.
5Mark the date on the container. Write the current date out on the container using permanent marker. By marking the date on the jar, you will be able to keep track of how long the seeds have been in storage.
- Note that you should also mark the cultivar name and type of plant on the container, especially if you grow multiple plant varieties.
6Freeze the seeds. While this may seem counter-intuitive, rather than hurting the seeds, freezing them actually keeps them cool and minimizes the amount of humidity. Humidity is your worst enemy if trying to save heirloom seeds. As such, freezer storage is ideal. This is especially true if you store the seeds in a freezer that is rarely opened.
7Store seeds of different varieties separately. You do not want different varieties to get mixed up. If this occurs, you will end up growing different varieties of the same plant too close together, leading to cross-breeding and ruining your chances of collecting heirloom seeds later on.
8Thaw the seeds out before use. Before using them, all the seeds to thaw out to room temperature. Then plant as normal.
- Maintain the purity of your heirloom seeds by keeping different varieties separated. If possible, only grow one variety per plant type in your garden. If you do grow multiple varieties, however, you should keep them as far apart as possible. Many plants will cross-pollinate or cross-breed, and as a result, the seeds they produce will no longer be considered heirloom seeds.
- Understand that the longer you store heirloom seeds, the less viable the seeds will be. Most seeds will begin to lose viability after three years. Even under the best storage conditions, seeds begin the lose energy as they remain in storage. The root systems of stored seeds will be especially damaged.
- Seeds that are not completely dry are likely to develop mold or mildew in storage. Mold and mildew will ruin the seed’s ability to sprout.
Things You’ll Need
- Newspaper or paper towel
- Silica gel
- Glass jars with lids
- Freezer-safe containers or bags
- Diatomaceous earth
- Permanent marker