Why Save Seeds?
Seed saving is a practical and time-honored tradition. Gardeners save seeds to reduce costs, preserve favorite or rare varieties, and pass down heirlooms through generations. It helps maintain genetic and cultural diversity, allowing gardeners to adapt plants to local conditions and support biodiversity.
As commercial seed sources consolidate and crop diversity declines—75% lost since 1900—seed saving becomes increasingly important. Despite 30,000 edible plant species, just 30 provide most of our calories. By saving seeds, gardeners protect unique varieties and strengthen food resilience.
Seed saving also builds community by encouraging the exchange of seeds and knowledge. It fosters creativity, self-reliance, and a deeper connection to the natural cycle of life—a living legacy for the future.
The Importance of Seed Diversity
A reliance on just a few plant varieties poses risks to our food systems. Historical events, like the Irish potato famine—where a dominant single variety was wiped out by disease—show the dangers of limited genetic diversity. Today, a few large companies control most of the seed market, often selling hybrid seeds bred for uniformity and mass production. This has increased food production but reduced the diversity safeguarded by traditional seed-saving.
Saving seeds preserves heirloom varieties and supports local adaptation. It’s a cost-effective way to access a wider variety of plants. Seed libraries and exchanges allow gardeners to trade seeds, further enhancing local resilience and crop diversity.
What Is a Seed?
A seed is, fundamentally, an embryonic plant encased in a protective covering along with stored food to fuel its germination. Germination is triggered by moisture and warmth, awakening the dormant plant within. Proper storage—cool and dry—is crucial, as seeds lose viability when exposed to heat and moisture. Most seeds last at least two to three years if stored correctly, with some remaining viable for much longer.
Seed Types and Plant Life Cycles
Understanding the life cycle helps determine when and how to collect seeds.
- Annuals complete their life cycle in a single growing season, producing seeds quickly.
- Biennials require two years to mature and set seed, often needing a period of cold before flowering. If they are planted in the spring, summer, or fall of the year, they will not flower and go to seed until the following spring. In California’s mild winters, these plants can be left in the ground all winter and allowed to flower and produce seed the following spring.
- Perennials live for many years, flowering and producing seeds over multiple seasons. They are available in a huge variety of colors, textures, forms, and fragrances. Perennials are dependable and easy.
Pollination Fundamentals
Open pollination (OP) refers to the process where plants are naturally pollinated through either cross-pollination or self-pollination. Open-pollinated especially among related crops (e.g., squashes, brassicas, peppers, corns) may require isolation techniques or manual pollination. Plants pollinate in different ways:
- Self-pollinating plants (like tomatoes, beans, peas) have both female and male parts and can pollinate themselves. They are easiest to save seed from, as they rarely cross with others.
- Cross-pollinated plants (like corn, squash) are pollinated by wind, water, or pollinators like bees or other insects require isolation or distance from other varieties of the same species from other varieties to maintain purity. Mechanical isolation with screen cages or bags is usually the best option. This may necessitate some hand-pollinating, since insects may not be able to reach the flowers.
Heirloom varieties are best for seed saving, as their seeds replicate the parent plant’s traits.
DO NOT save seed of hybrid plants. Hybrid seeds (F1) do not produce offspring true to type and are unsuitable for saving.
Getting Started with Seed Saving
Plan ahead by choosing suitable plants for seed saving and understanding their pollination and growing needs. Select the healthiest plants with the traits you wish to preserve—such as disease resistance, flavor, or productivity. Grow enough plants to maintain genetic diversity, especially for cross-pollinated crops.
Save vegetable seeds from your garden produce to plant next year. Seed saving involves selecting suitable plants from which to save seed, harvesting seeds at the right time and storing them properly over the winter. The UC Master Gardeners of Placer County has created a Saving Seeds table that provides detailed information about saving vegetable seeds.
When and How to Harvest Seeds
Allow seeds to reach full maturity on the plant. For dry-seeded crops like beans and lettuce, wait until pods and seed heads are brown and dry. For wet-seeded crops like tomatoes and cucumbers, leave fruits on the plant until fully ripe, then extract and clean the seeds.
Collect seeds only from the healthiest, most desirable plants. Look for maturity signs such as hard seed coats, dry pods, or color changes. Harvest seeds before they are dispersed or fall victim to wildlife.
Cleaning and Drying Seeds
Dry seeds are separated from their pods, husks, or flower heads (threshed) and winnowed to remove debris--separating the heaver parts from the lighter ones with the help of wind. Damage begins to occur whenever the temperature of seeds rises above 95°F. Fans accelerate the drying process. Place seeds on window screens to allow for excellent air circulation.
Wet seeds, such as those from tomatoes and cucumbers, should undergo fermentation to remove germination inhibitors prior to washing and thorough drying. The fermentation process involves removing seeds from fruit, adding water if too thick to stir, then placing the seed/pulp mixture in a container in a warm location (72°F-86°F) for 2-5 days, stirring daily. When bubbles form on the surface. To separate the seeds, add water to the container. Viable seeds will sink. Rinse thoroughly. Ensure seeds are dried completely indoors on glass, ceramic, or metal surfaces to prevent sticking and facilitate removal. Avoid drying seeds on paper towels or cloth, as these materials make separation difficult; instead, coffee filters are recommended since seeds do not adhere to them. Distribute the cleaned seeds evenly on a non-stick surface, occasionally stirring them until they are fully dry.
To prevent disease, only save seeds from healthy plants. If there’s a risk of insect infestation, freeze fully dried seeds for a few days before storing.
Seed Storage Best Practices
Store seeds in airtight glass containers, using paper packets for different varieties. Add a desiccant, such as silica gel or powdered milk, to absorb residual moisture. Keep seeds labeled with their name, variety, and collection date, and store in a cool, dry, and dark place—ideally between 32° and 41°F.
While most seeds remain viable for two to three years, some last much longer. Proper storage maintains seed vigor and germination rates. Avoid plastic bags, as trapped moisture can promote mold growth.
Special Seed Treatments
- Scarification: Physically breaking the hard seed coat to enable germination.
- Soaking: Softening the seed coat and leaching inhibitors.
- Stratification: Providing a cold period to break dormancy in some seeds.
Some seeds require combinations of these treatments for successful germination.
Six Tips for Success
- Choose only the healthiest, most desirable plants for seed saving.
- Save seeds only from open-pollinated varieties, not hybrids.
- Keep detailed records about each seed variety and growing season.
- Be vigilant about cross-pollination.
- Maintain adequate plant populations to ensure genetic health.
- Store seeds properly to maximize longevity and viability.
By following these principles, gardeners can contribute to global biodiversity and enjoy the many rewards of seed saving.