How to Save Tomato Seeds.

How to save tomato seeds Heirloom tomato assortment

Ah, fall. While most gardeners turn their attention to arranging pumpkins on porches and planting brassicas, I’m busy obsessing over tomatoes.

Tomato seeds, that is.

How to save tomato seeds bowl of heirloom tomatoes

This summer, the garden produced a bounty of deliciousness. Thai Pink Egg, my husband’s favorite, filled four bowls on the counter one week. Pineapple, with its gorgeous pink interior and golden, striped flesh, created some of the prettiest caprese salad we’ve eaten. Adorable purple Bumblebee cherries added interesting color to bruschetta. The rainbow of tomatoes, in all shapes, sizes, and colors, always amazes me. It makes me wish that I could paint, because “Still Life with Heirloom Tomatoes” would make a lovely addition to brighten our kitchen during dreary winter days, when the taste of fresh tomatoes is just a memory.

How to save heirloom tomato seeds blossom on plant

Now, though, as cooler temperatures arrive in South Carolina and the tomato plants stand tiredly on their last legs, victims of drought and extreme heat, it’s time to enjoy those last few, ripe fruits—and preserve favorite varieties for next year’s garden.

How to save heirloom tomato seeds large variety

It’s time to save seeds.

For most gardeners, tomatoes serve as the gateway into the world of seed saving. After all, many of us begin gardening because we crave the taste of a just-picked, sun-warmed tomato, and we want to enjoy that deliciousness all summer. Plus, once we discover a tomato with a unique, favorite flavor, we want to ensure its continued place in our gardens—and on our plates. With the thousands of varieties of heirloom tomatoes available throughout the world, there’s no end to discovering a new-to-you, tasty treat to add to your garden.

The beauty of saving tomato seeds resides in the timing. When tomatoes are ready to harvest and eat, the seeds are ready for preserving, too. There’s no need to leave some fruit on the vine, awaiting it to dry or overripen, like with saving seeds of eggplants or beans. Instead, saving tomato seeds can happen while preparing your heirlooms for dinner—with zero waste.

How to save heirloom tomato seeds close up seed

Tomato seeds are enclosed in a gelatinous sack, which contains chemicals that inhibit germination inside the tomato. In nature, a tomato falls off the vine, decomposes, and natural fermentation destroys the gel sac, allowing the seed to germinate in ideal conditions.

To save tomato seeds, we simply mimic nature, fermenting the tomato seeds to remove the gel sac. It’s a simple, if smelly, process, but fermentation also kills many seed-borne tomato diseases. While the odor may be unpleasant, saving heirloom, open-pollinated tomato seeds is simple.

  • Wash fruit.

  • Slice tomato through the middle horizontally, not through the blossom end and core. This will expose the seed cavities.

How to save heirloom tomato seeds extricating seeds from fruit

  • Squeeze the seeds and surrounding gel into a bowl or canning jar.

  • Label each jar with the name of the tomato variety.

  • If you’re saving more than one variety of tomato seed, make certain to carefully clean your cutting board, knife, and strainer to avoid mixing seed varieties.

  • For small tomatoes, like cherry or currant tomatoes, place the entire fruit in a blender and process on low speed. The small seeds won’t be damaged. Pour into a bowl or jar as above.
    How to save heirloom tomato seeds add water

  • Add ½ cup of water to the jar, and stir into seed mixture.
    How to save tomato seeds label the jars

  • Let stand for 1-3 days.

How to save tomato seeds fermentation

  • As the mixture ferments, a layer of white or grayish mold appears. The process is done when the mold covers the surface. (Don’t over-ferment, as seeds may begin to germinate if left too long.)

  • Add 1 cup of water, and stir the mix. Beware: it smells terrible.

  • Let mix settle. Viable seeds will settle to the bottom, while hollow seeds float to the top of the mix. Remove the duds with a spoon.

How to save tomato seeds pour into strainer

  • Pour mix into a fine-mesh strainer, rinsing with water until seeds are clean from debris.

  • Pat the excess water from the bottom of the strainer with a paper towel.

How to save tomato seeds dry on paper plate

  • Pour the clean seeds from the strainer onto a plate. Spread seeds into a single layer to dry. Label each plate with the tomato variety.

  • Stir seeds several times per day to ensure complete, even drying. Separate any clumps that form.

  • When seeds are completely dry (approximately one week), store seeds in an air-tight container in a cool, dry area, or freeze for long-term storage. Make certain to label your seeds carefully for accuracy.

*Note: Do not dry seeds in oven or direct sunlight.

Personally, I multi-task. I slice the tomatoes, squeeze the seeds into the containers, and then proceed to dice the tomatoes for bruschetta or salsa. Yes, the tomatoes do get a bit mangled while seed saving, so if presentation is important, like for a lovely caprese salad or tart, you may wish to forgo saving seeds from those tomatoes.
How to save heirloom tomato seeds for self sufficent gardens

Saving the seeds of just one tomato can provide you with plants for many years. And, with so many thousands of heirloom tomato varieties, you may soon find yourself with a large seed library. You’ll have plenty of seeds to share with family, friends, and neighbors. Sharing seeds is almost as much fun as sharing the garden’s bounty.

Seeds are a good addiction. Maybe one day, you’ll grow 184 varieties of heirloom tomatoes, like me. Or maybe you’ll preserve your sanity, grow four or five of your favorite tomatoes, and enjoy your summer. lounging by the pool. No matter your seed obsession level, it’s a fabulous, self-sufficient feeling to grow a garden from seed you’ve saved.

Do you have a favorite seed story? Stay tuned, because coming in Fall 2018, I'll be sharing my seed starting and saving tips in a book published with Cool Springs Press!

Happy Growing!