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How to Save Your Vegetable Seeds for Next Year

Learn to save vegetable seeds for years to come.

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The Spruce / Michelle Becker

A packet of vegetable seeds may look dry, brittle, and lifeless, but in many cases, seeds are very much alive. Inside each plant seed is the embryo of a future plant. However, seeds do not remain alive forever. How long seeds remain viable depends on the type of seed and how well it is stored.

Most Vegetable Seeds Can Stay Viable for Years

Most vegetable seeds remain good for about two to three years, but some, such as onions, deteriorate within a year and others such as lettuce, can successfully sprout after five years. The table below lists average years of viability for well-stored vegetable seeds, compiled from regional sources. There will be some variability because of the variety of seed and whether the seed was fully ripe and kept dry in storage.

Seed Storage Guidelines

Vegetable Storage Years Vegetable Storage Years
Arugula 4 Leek 2
Bean 3 Lettuce 5
Beet 4 Muskmelon 5
Broccoli 3 Mustard 4
Brussels Sprouts 4 Okra 2
Cabbage 4 Onion 1
Carrot 3 Parsley 1
Cauliflower 4 Parsnip 1
Celeriac 3 Pea 3
Celery 3 Pepper 2
Chard, Swiss 4 Pumpkin 4
Chicory 4 Radish 4
Chinese Cabbage 3 Rutabaga 4
Collards 5 Salsify 1
Corn Salad 5 Scorzonera 1
Corn, Sweet 2 Sorrel 4
Cucumber 5 Spinach 2
Eggplant 4 Squash 4
Endive 5 Tomato 4
Fennel 4 Turnip 4
Kale 4 Water Cress 5
Kohlrabi 3 Watermelon 4

How to Store Vegetable Seeds

You can’t do anything to change the life expectancy of different types of seeds. But if you save your own seed or need to store purchased seed, you can keep it fresh for the maximum amount of time by taking these steps to store it properly.

  • Be certain the seeds are completely dry, to the point of being brittle, before you pack them away.
  • Place dried seeds in a paper envelope, to absorb any moisture that might get in, and label with the name and year.
  • Keep the envelopes in an airtight container out of direct sunlight.
  • Store in a cool, dry place.

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The Spruce / Michelle Becker

How to Test Seeds for Viability

There’s an easy way to determine how viable your saved seed is and what percentage of it you can expect to germinate.

You Will Need:

  • 10 seeds
  • Paper towels
  • Water
  • Sealable plastic bag
  • Permanent marker

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The Spruce / Michelle Becker

Moisten a sheet of paper towel so that it’s uniformly damp, but not dripping wet.

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The Spruce / Michelle Becker

Place the 10 seeds in a row along the damp paper towel.

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The Spruce / Michelle Becker

Roll or fold the paper towel around the seeds so that they are covered.

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The Spruce / Michelle Becker

Place the paper towel with the seeds into the plastic bag and seal it. Write the date on the plastic bag, so there’s no guesswork involved. If you are testing more than one type of seed, also label the bag with the seed type and variety.

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The Spruce / Michelle Becker

Place the plastic bag somewhere warm, about 70 degrees Fahrenheit (a sunny windowsill or on top of the refrigerator should work).

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The Spruce / Michelle Becker

Check daily to be sure the paper towel does not dry out. It shouldn’t because it is sealed, but if it gets very warm, you may need to re-moisten the towel with a spray bottle.

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The Spruce / Michelle Becker

Start checking for germination in about five days. To do this, gently unroll the paper towel. You may even be able to see sprouting through the rolled towel. Very often the roots will grow right through it.

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The Spruce / Michelle Becker

Check your seed packet for average germination times for your particular seed, but generally, 7–10 days should be enough time for the test.

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The Spruce / Michelle Becker

After 10 days, unroll the paper towel and count how many seeds have sprouted. This will give you the percentage germination you can expect from the remaining seeds in the packet. If only three sprouted, it is a 30% germination rate. Seven would be a 70% germination rate, nine would be a 90% germination rate, and so on.

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The Spruce / Michelle Becker

What the Germination Rate Tells You

Realistically, if less than 70% of your test seed germinated, you would be better off starting with fresh seed.

If 70–90% germinated, the seed should be fine to use, but you should sow it a little thicker than you normally would.

If 100% germinated, your seed is viable and you’re ready to plant.

There is no need to waste the seeds that have germinated; they can be planted. Don’t let them dry out and handle them very carefully so that you don’t break the roots or growing tip. It’s often easiest to just cut the paper towel between seeds and plant the seed, towel and all. If the root has grown through the towel, it is almost impossible to separate them without breaking the root. The paper towel will rot quickly enough and, in the meantime, it will help hold water near the roots.

Many vegetable seeds can be viable for years if they're stored properly. Learn how long each type of seed can survive and how to store and test them.

Do Seeds Expire and Go Bad?

Related Articles

Part of managing this year’s garden is thinking about next year’s seeds. You may be able to use leftover seeds from this year’s garden in next year’s plan. Or you might be able to save seeds from this year’s harvests. In very general terms, like other living things, seeds can become damaged or diseased and die. The rate at which they lose viability varies by seed type and, most important, storage conditions.

Viability Lore and Science

Legends assert that plants have grown from seeds found in ancient city ruins and royal tombs. Perhaps best known are accounts of lotus seeds found in a Manchurian lake bed, sprouted successfully after 1,200 or more years; in 2002, two Manchurian lotus seeds over 400 years old were grown into mature plants at Brookhaven National Laboratory. According to the U.S. Forest Service, more realistic estimates set the length of time most seeds can remain viable at approximately 150 years. The Kew Royal Botanical Gardens Millenium Seed Bank, a worldwide seed conservancy project, regularly tests many varieties of seeds for viability every five to 10 years. Past and ongoing studies of found seed stashes suggest that numerous members of the bean family (Leguminae; Fabaceae) and grass family (Graminae; Poaceae) may be viable after 40 to 70 years (see References 7, 8 and 9). Not surprisingly, a number of these are commonly regarded as weeds.

Estimating Garden Seed Viability

Scientists classify the lives of seeds as microbiotic, or less than three years; mesobiotic, from three to 15 years; and macrobiotic, 15 years or more, although many factors makes these categories only approximations. Most garden seeds fall into the first two categories; and seeds of plants consumed in their entirety as food, like onions, tend to be the most short-lived. Because of the critical importance of seeds as food sources, home gardeners will likely find more generally accepted information on vegetable seeds than on flowers. Oregon State University Extension, for example, offers only a general guideline for flower seeds, estimating a viability of a year or two for annuals and two to four years for perennial flowers.

Vegetable Seed Viability

A comparison of estimates from two seed producers and two university extensions divided vegetables roughly into three categories. Seeds regarded as viable for one to three years were beans, carrots, corn, leek, onion, parsnip, parsley, spinach, peas and peppers. Those viable for three to five years were beets, brassicas, celery, chard, eggplant, lettuce, cucumber, radish, squash and pumpkin. Generally, tomato, muskmelon and watermelon seeds were considered viable for five to 10 years.

Factors Affecting Viability

In some ways a seed needs to be treated like the plant it will become. Extreme temperatures and excessive moisture are equal threats to seeds. Excess moisture can produce mold or foster fungal diseases and rot in the seeds of most plants that grow in temperate zones (U.S. Department of Agriculture plant hardiness zones 3 through 9), while seeds of plants from subtropical and tropical climate zones (zones 10 and 11) may require high humidity to survive. Cool, dry, dark, clean conditions are necessary to store most temperate-climate seeds, whether purchased from commercial growers or collected from your garden. Keeping seeds in sealed containers prevents mold spores or other airborne organisms from infecting them. Some experienced seed-savers save refrigerator space for winter seed storage. For tropical or non-native plants, information from seed packets, grower sites and botanical gardens can help you provide variety-specific storage for seeds.

Viability-Enhancing Strategies

For successful seed saving, wait until seeds are fully mature before harvesting them. No matter how carefully stored, immature seeds lack the ability to become new plants. With vegetable seeds, for example, wait until vegetables are slightly past their prime; the seeds of a wrinkled pepper or overripe tomato are mature and ready for storage. Typical seed-packet directions include the length of the typical germination period, usually within 14 days for annuals, and often indicate a soil temperature desirable — and sometimes essential — for germination. Even perfectly viable seeds may not germinate with the wrong soil temperature, water or light. Seeds with very hard outer coverings may benefit from being scraped with a knife blade or sandpaper. Others need the artificial wintering known as cold-stratification, in which seeds spend weeks to months between layers of chilled moist soil or planting medium. Still others germinate faster after being soaked.

Do Seeds Expire and Go Bad?. Part of managing this year’s garden is thinking about next year’s seeds. You may be able to use leftover seeds from this year’s garden in next year’s plan. Or you might be able to save seeds from this year’s harvests. In very general terms, like other living things, …