Seed Saving from The Webster Arboretum

A new hobby to consider this fall is seed saving. This practice, which dates back more than 10,000 years to the origins of agriculture, involves collecting seeds from cultivated plants to secure future harvests. Early farmers selected seeds from the most resilient plants, preserving them for subsequent seasons—an approach that enabled crops to adapt to local environments and increase yields over millennia. Today, this time-honored tradition continues among modern gardeners as they engage in the art of seed saving.

Check out organizations such as Seed Savers Exchange, one of the largest nongovernmental seedbanks in the United States, dedicated to the preservation of heirloom seeds.  This site provides a great deal of information on seed saving and provides the opportunity to share and swap unique varieties of seeds you might not find anywhere else.

Did you grow the perfect tomato this year? Are your cucumbers to die for?

Seed saving maintains preferred plant varieties, supports food security, sustainability, and cultural practices. It can save costs and increase garden biodiversity through exchanging seeds—especially for varieties not commercially available.

Let’s get started… Many plants, like tomatoes, peppers, beans, peas, cucumbers, melons, and various herbs and flowers, are ‘ripe’ for seed saving. Collect mature seeds after plants have fully grown and dried—usually late summer to fall. Dry seeds thoroughly before cleaning and store them in a labeled, air-tight container, such as a small jar or envelope in cool, dark, dry places.   

How to Save Seeds

• Allow root vegetables and greens (carrots, radishes, lettuces, etc.) to bolt, collect dried flowers, and catch seeds. Simply shake in paper bag to release seeds.

• For herbs (basil, dill, cilantro, chamomile), let pods or flower stalks dry, then gather and store seeds; don't worry about separating tiny flowers from seeds.

• Save tomato seeds and other fruits or vegetables with gel coated seeds such as cucumbers or melons by scooping out the seeds and gel, fermenting in water for a few days, rinsing, drying, and storing. (see information below)

• Peppers should be fully ripe—simply open, extract, dry, and store seeds.

• Beans and peas need to be left on the vine until pods are crunchy dry before harvesting seeds; avoid letting the pods burst as your seeds will be lost.

General Steps

• Harvest only fully mature, dry seeds on a dry day with clean tools.

• Separate seeds from debris and discard damaged ones.

• Dry seeds in a well-ventilated area; ensure they snap or shatter when fully dry. If seeds are stored before they are fully dry their viability will be compromised.

• Store seeds in cool, dark, and dry conditions—refrigeration is possible if moisture is controlled. Use opaque containers to block light.

Seed viability depends on the type of plant; parsnips and onions typically remain viable for only a few years, while cabbage and squash seeds can last five years or longer with proper storage. Tomato seed viability is generally 3-5 years but can extend to 10 years under ideal storage conditions

Tomato and other fruits with seeds enclosed in a gelatinous solution

1.    Choose a good-quality, mature fruit: Select a fully ripe, healthy fruit from your best-looking, non-hybrid (heirloom) tomato plants.

2. Extract the Seeds

• Cut the tomato: Slice the tomato in half across the middle. 

• Scoop out the seeds: Squeeze the seeds and pulp into a clean jar. 

3. Ferment the Seeds

·      Add a little water to the jar to create a watery slurry and label it with the tomato variety. 

• Let the mixture sit in a warm place for 3-5 days, stirring once a day, until a layer of white mold or fungus forms on the surface. This process dissolves the naturally protective coating around the seeds. 

4. Clean the Seeds

• After fermentation, add more water to the jar and stir to loosen the viable seeds from the pulp and mold. 

• Pour off the water, pulp, and floating seeds (unviable seeds) while retaining the good seeds that sink to the bottom. Repeat until the seeds are clean. 

5. Dry the Seeds 

• Spread on a plate: Pour the clean seeds into a fine-mesh strainer, rinse them, and then spread them in a single layer on a sheet of paper (like label paper or computer paper). Don’t use paper towels as the seeds may stick to it.

• Allow to dry completely usually 1-3 days

6. Store the Seeds

• Place the completely dry seeds into a labeled, air-tight container, such as a small jar or envelope. 

• Store the containers in a cool, dry area, away from direct sunlight, to preserve their viability for several years