How to Save Tomato Seeds: Keep Your Favorite Varieties Growing

Seed saving heirloom open pollinated tomato

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Seed saving heirloom open-pollinated tomato.

Photo Credit
Tinus Potgieter
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Never lose your favorite varieties by saving tomato seeds.

Written By: Robin Sweetser Gardener

Love that one special tomato you grow every summer? Saving its seeds ensures you’ll always have it, even if it disappears from catalogs. With many older varieties fading out, seed saving is a smart, sustainable way to keep your favorites growing for generations—just like gardeners have done for centuries. Keep reading to learn how to save tomato seeds.

Saving Seeds: A Time-Honored Tradition

Long before commercial seed catalogs, early settlers and pioneers—including famous gardeners like Thomas Jefferson—relied on saving tomato seeds to preserve favorite varieties and ensure a reliable harvest. Many heirloom tomatoes we cherish today are the result of generations of seed saving, passed down like treasured family recipes. I have been saving seeds for many years, carefully selecting the best from my fruits. My tomatoes continue to improve year after year.

Benefits of Saving Tomato Seeds

It is a process that is easy enough to do and will give you a measure of security, knowing that those seeds will be available for you to plant and share with friends and family. You can choose which plants to save seeds from based on the qualities that are most important to you, such as flavor, fruit size, disease resistance, earliness, high yields, or ease of cultivation. Over the years, your plants may also adapt to your growing conditions.

I have found that my home-saved seeds germinate better and faster than store-bought ones. I assume it is because they are fresher and were carefully stored. Like everything else, seeds are getting more expensive, so saving your own seeds can save you some money too! 

Heirloom tomato sliced open
All heirlooms are open-pollinated and perfect for seed-saving. Credit: Julie Vader

Which Types of Tomato Seeds Can Be Saved?

To ensure success, only save seeds from open-pollinated varieties of tomatoes; all heirlooms are open-pollinated. They will reliably give you fruit with the traits of the parent plant. Don’t save seeds from hybrid plants. Since they were created by intentionally crossing two different varieties, their seeds are unpredictable and won’t produce that specific fruit again. The new plants may bear tomatoes resembling those of one parent or the other, or be a throwback to a distant relative. It will not be the same as the fruit you chose to save. If you are feeling adventurous, you can give it a try. Who knows! You may develop a fantastic new tomato, but chances are, you will be disappointed. Often, hybrid seeds are sterile, and you will get no plants at all.

seed packets listing heirloom tomato names.
Both the Mortgage Lifter and Black Krim tomatoes are heirloom beefsteak tomato varieties. Credit: Robin Sweetser

Mind the Gap

If you are serious about saving seeds, be mindful of how closely you plant other tomato varieties. Tomatoes are mostly self-pollinating, with a little help from the wind and bumblebees shaking the blossoms, but they could unintentionally cross with a nearby variety, so plant the one you want to save seeds from at least 10 feet away from other types of tomatoes. Learn more about understanding the distance between plantings

How to Save Tomato Seeds

Tomato seeds must be fermented in water for a few days to remove the gelatinous coating around them. This simulates the natural rotting of the fruit. Fermentation also kills many seed-borne diseases and stimulates germination. It will be stinky! You might not want to do it in the house with the windows closed. Follow these simple steps:

  1. Choose an overripe, soft but not mushy tomato.
  2. Scoop or squeeze the seeds into a bowl or glass jar.
  3. Add roughly the same amount of water as tomato pulp to the jar and stir.
  4. Let the bowl sit at room temperature, out of sunlight, for 3 to 5 days.
  5. Gently stir daily, but don’t be alarmed if mold forms on the top.
  6. Once most of the seeds have settled to the bottom, scoop off the mold and any floating seeds—they are “duds” and will not germinate, so throw them away.
  7. Pour the rest into a strainer to drain, and rinse them thoroughly with clean water to remove any remaining gel.
  8. Allow the seeds to dry on a fine screen, out of direct sun, for a week or two until they are completely dry.
  9. Test the seeds for dryness by trying to snap them in two. If they just bend, they need more drying time.
  10. Store your dried seeds in a paper envelope and keep them in a dark dry place until it is time to plant. Be sure to label and date them.
  11. Tomato seeds are viable for up to 5 years. Germination rates will start to decrease as the seeds get older.
Close-up of small tomato seeds drying on a fine screen.
Tomato seeds drying on a fine screen. Credit: Robin Sweetser

Related: Growing Tomatoes in Pots

Tips for Successful Seed Saving

  • Only save seeds from an open-pollinated plant.
  • Choose a fruit that is fully ripe.
  • Storing your seed packets in an airtight container in the fridge will keep them viable longer.

Troubleshooting Common Issues

  • Unsure if the fruit you want to save is open-pollinated or a hybrid? Look up the name of the tomato online or in a seed catalog. It will be labelled as F1 if it is a hybrid.
  • Don’t save seeds from a sickly plant. It may carry genetic defects.
  • If the fermenting pulp is drawing insects, cover the bowl or jar with a coffee filter or paper towel held in place with a rubber band to keep them out.
  • Wet seeds will stick to plastic or ceramic plates. It is better to dry them on fine screening so air can circulate around them.
  • Keep your seeds as dry as possible in storage to prevent them from getting moldy.
Beautiful photo showing a variety of heirloom tomatoes.
Saving tomato seeds helps preserve the unique flavors and characteristics of heirlooms. Credit: Shebeko

What to Do With Your Saved Seeds

Once your tomato seeds are dry and labeled, don’t just stash them away and forget about them—put them to good use!

  • Plant them next season: Start your seeds indoors in late winter or early spring, just as you would with store-bought seeds. You’ll get the added satisfaction of knowing your plants came full circle—from seed to fruit and back again. Read our 12 simple steps to starting tomato seeds inside.
  • Share with others: Pack a few envelopes to give to fellow gardeners, family, or friends. Tomato seeds make thoughtful, personal gifts—especially if you include a note about why you love that variety. Some folks even create homemade seed packets with photos or growing tips.
  • Join a seed swap: Seed swaps are a wonderful way to connect with your community and discover new varieties. My local library started a seed swap! Garden clubs and online forums also host swaps during the off-season. You might trade a favorite tomato for a unique pepper or flower you’ve never tried!

There is a reason why gardeners have saved seeds from their favorite tomatoes and passed them down over the years. It is a great way to preserve the best fruit for yourself and future generations to enjoy! 

Are you ready to start growing with your saved tomato seeds? We’d love to hear from you in the comments below!

About The Author
Robin Sweetser

Robin Sweetser

Gardener

Robin Sweetser is a longtime gardening writer, editor, and speaker. She and her partner, Tom, have a small greenhouse business, selling plants and cutting flowers and vegetables from their home and lo...