Last Updated on October 9, 2026

Seed Saving Chart: Which Vegetables Are Easy to Save

Beans, peas, lettuce and tomatoes are the easiest vegetable seeds to save. They are annual and self-pollinating, and you only need a few plants to get good seed. That is how University of Illinois Extension sorts them. Squash, cucumbers, melons and corn cross with other varieties, so they need distance or bagged flowers. Carrots, beets, onions and cabbage are biennials and take two seasons. Whatever you save, start with open-pollinated or heirloom seed, because hybrids do not come true.

Seed saving chart

Sources. Life cycle, pollination and isolation distance: the Seed Savers Exchange chart in University of Illinois Extension’s How to Save Seeds. *Eggplant is not on Illinois’ chart, so that row uses the UC Master Gardeners of Placer County chart, which flags eggplant as self-pollinated but still able to cross, which is why it still needs 150 ft of distance even though it is listed as easy. Wet or dry: University of Georgia Extension, Illinois, and Washington State University Extension’s seed saving guide, which also notes beets and chard are one species and cross. Years viable: my seed viability chart, for seed stored cool and dry.

Difficulty. “Easy” is Illinois Extension’s list of annual, self-pollinating crops. “One variety at a time” is the other annuals marked self or insect, since insects can still move pollen. “Needs isolation” means insects or wind carry it. “Two seasons” means the plant flowers in its second year.

Start with open-pollinated seed, not hybrids

In my guide to choosing the right seeds, open-pollinated seed is the one to grow if you want to save your own, since it grows plants like the parent. Hybrids are the opposite: their seed grows plants with unpredictable traits.

• Open-pollinated: ‘Brandywine’, ‘San Marzano’ and ‘Big Rainbow’ tomatoes, ‘California Wonder’ peppers, ‘Little Marvel’ peas, and ‘Kentucky Wonder’ and ‘Blue Lake’ beans are open-pollinated varieties that come true from seed, per University of Minnesota Extension.
• Heirlooms are open-pollinated varieties passed down through generations for a trait like taste or color, per Illinois Extension.
• Hybrids are usually labeled “hybrid” or “F1” on the packet, per Illinois Extension. Hybrid tomatoes like ‘Big Boy’ and ‘Early Girl’ do produce viable seed, but the plants they grow are not identical to the parent, and there is no way to predict how they will turn out, per University of Minnesota Extension.

Beans are the easiest place to begin. Wood Prairie’s organic Celine bean is listed as an heirloom bush bean (my Celine bean spotlight has more on it). Use code PMG5 for 5 percent off.

How to keep varieties from crossing

For squash and cucumbers, crossing does not hurt this year’s fruit, but seed from a crossed vine grows fruit unlike the parent, often with worse flavor, per University of Minnesota Extension. Corn is the exception: popcorn pollen in sweet corn changes that year’s flavor. Only varieties within the same species cross, so a cucumber will not cross with a squash or a watermelon, per Illinois Extension. Isolation works by distance, time or containment, and the chart above covers distance. How many plants of a variety you grow also matters: for cucurbits (squash, cucumbers and melons), save seed from 5 to 10 plants to maintain a variety over time, or from 25 plants if you are preserving a rare one, per SDSU Extension. Without enough distance, you have three options:

1. Grow one variety. Save one variety of a species per season, a favorite cabbage one year and a broccoli the next, since stored seed stays good for years, per Seed Savers Exchange.
2. Change the timing. Stagger plantings so two varieties do not flower at the same time. This works only for crops like corn that flower over a short, even window, per Seed Savers Exchange.
3. Cover the flowers. Use paper bags, nylon bags or floating row cover over the flowers to keep stray pollen out, then move the pollen by hand with a cotton swab or small paintbrush, per Illinois Extension. Seed Savers Exchange names tomatoes, peppers and eggplant as easy crops to blossom-bag.

For squash, South Dakota State University Extension‘s method: tape or bag male and female flowers shut just before they open, hand-pollinate early in the morning within 4 hours of the female flower opening, then close the female flower again and mark that fruit.

Distances vary by source: UGA Extension’s home garden table gives 10 feet for tomatoes and bush beans and 160 feet for sweet peppers, while the chart above uses Illinois’ wider numbers. Colorado State University Extension notes commercial seed growers follow these guides most closely, but home gardeners who ignore them will be disappointed.

Wet processing: tomatoes, cucumbers, squash, melons

Wet seeds sit in the flesh of the fruit and have to be cleaned out of it. Fermenting them lets bacteria and yeast destroy many of the seed-borne diseases that would carry into next year’s plants, per Washington State University Extension. The steps below follow University of Minnesota Extension for tomatoes and peppers, UGA Extension for the tomato drying time, and SDSU Extension for cucumbers, squash and melons.

• Tomatoes. Let the fruit ripen fully, then ferment the seeds and gel in a jar of water for about five days, stirring twice a day, then rinse and dry them on a coffee filter or screen for about a week.
• Cucumbers. Pick the fruit several weeks after it matures and turns yellow or orange. Scoop the seeds and pulp into water and ferment 2 to 4 days at room temperature, stirring now and then. Add more water, pour off the pulp and any floating seeds, and dry what sinks. They are ready when they snap cleanly in half.
• Squash and pumpkins. Store the fruit until it starts to lose eating quality, then ferment the seeds the same way as cucumbers. Leave summer squash on the plant until the rind hardens.
• Melons. Leave the fruit on the vine 1 to 2 weeks after it matures, then wash the seed by hand and dry it.
• Peppers. Leave some fruit on the plant until it is fully ripe and starts to wrinkle, then remove the seeds and spread them out to dry.

When you sow saved tomato seed the next spring, my Sweetie tomato guide covers germinating it at 70-75°F, and the germination temperature chart has the rest of the crops.

Dry processing: beans, peas, lettuce and the rest

The steps below follow University of Minnesota Extension for beans and peas and WSU Extension for lettuce, spinach, beets, chard and cleaning.

• Beans and peas. Leave the pods on the plant until they are dry, turning brown, and the seeds rattle inside; that can take as long as a month after you would normally pick them to eat. Strip the pods and dry them indoors for at least two weeks before shelling, or leave the seeds in the pods until planting time.
• Lettuce, spinach, beets and chard. Let the seeds dry on the plant, then collect them. Spinach plants are either male or female, so let many plants flower at once.
• Cleaning. Thresh dry seed out of the pods or heads, sift it through a screen, and winnow off the light chaff.

Biennials take the long route. Dig the roots in fall, store them at 32 to 45°F through the winter, and replant them as soon as the weather permits so they send up seed stalks, per Colorado State University Extension. Do not save carrot seed if Queen Anne’s lace grows nearby; the two cross, per WSU’s guide.

Dry, store and label

• Dry it gently. Seed damage begins once seed temperature passes 95°F, so never dry seed in an oven; spread it thin on a screen with good air flow, per WSU Extension.
• Seal it cold. Store saved seed in tightly sealed glass containers at 32 to 41°F, which makes the refrigerator a good spot, with a little silica gel in the jar to pull out moisture, per University of Minnesota Extension.
• Label everything. The saving steps in my seed organizer post are simple: put the dry seeds in a plastic bag or jar and label it with the plant name, variety and date harvested.
• Use it soon, then test it. The years in the chart are for well-stored seed. University of Minnesota Extension is more cautious with home-saved seed: use it within one year, since older seed germinates less and grows with less vigor. Before you trust an older jar, run the 10-seed germination test in my seed viability chart.

Save from your best plants only: skip weak, off-type or diseased ones and keep the most vigorous plants with the best-tasting fruit, per University of Minnesota Extension. Some cucurbit diseases travel inside the seed, so save those only from plants with healthy, normal-looking leaves and fruit, per SDSU Extension.

Quick questions

What vegetable seeds are easiest to save?

Beans, peas, lettuce and tomatoes. University of Illinois Extension lists them as annual, self-pollinating crops where you only need a few plants to get good seed. Peppers work too, but its chart gives them 300 to 1,600 feet from other pepper varieties because insects can cross them.

Can you save seeds from hybrid vegetables?

The seed will grow, but it will not come true. University of Minnesota Extension says hybrid tomatoes like ‘Big Boy’ and ‘Early Girl’ produce viable seed, but the plants are not identical to the parent and there is no way to predict the fruit. Look for “hybrid” or “F1” on the packet and save from open-pollinated or heirloom varieties instead.

What is the isolation distance for seed saving?

It depends on how the crop is pollinated. The Seed Savers Exchange chart in Illinois Extension’s guide gives 10 to 20 feet for beans, peas and lettuce, 10 to 50 feet for tomatoes, 300 to 1,600 feet for peppers, and 800 feet to half a mile for squash, cucumbers, melons and corn. Without that room, grow one variety, stagger flowering, or bag the flowers and pollinate by hand.

How do you save tomato seeds?

Let the fruit ripen fully, ferment the seeds and gel in a jar of water for about five days, then rinse and dry them before storing.

How long do saved seeds last?

Stored cool and dry, tomato seed lasts about 4 years, beans and peas about 3, peppers about 2 and onions about 1, per the Illinois Extension figures in my seed viability chart. University of Minnesota Extension is more cautious with home-saved seed and says to use it within one year.

Plant your saved seed on time

Saved seed goes back in the ground on the same schedule as bought seed. My seed starting calendar counts the weeks from your last frost, and you can look up your frost dates by zip code. Plan My Garden is free to start: enter your zip code, draw your beds, pick the beans, tomatoes and everything else you want to grow, and it places each plant at square-foot spacing and builds a planting schedule from your frost dates.

Related: Seed Viability Chart · Choosing the Right Seeds for Your Garden · The Best Seed Organizer · Seed Germination Temperature Chart