How to Save Tomato Seeds (3 Simple Methods)
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Saving tomato seeds from homegrown fruit is easy, saves money, and can help you grow resilient strains that are suited to your garden. Here are three simple methods to save seeds: the paper towel method, fermentation, and the washing soda method. Once saved, tomato seeds can be stored and used for many years to grow your own tomatoes!
It’s easy to spend a small fortune on tomato seeds each year, especially if you like growing lots of different varieties. Fortunately, saving seeds from homegrown tomatoes can save you a lot of money and leave you with enough seeds to share with friends and your community.
There are also at least three ways to save tomato seeds. All are easy, but one in particular takes only seconds. One technique involves drying seeds on a paper towel, another involves fermenting the seeds to break down their gel coating, and another simple method uses washing soda to clean the seeds.
We will also look at which tomato varieties to save seeds from and which to avoid. Choosing the right seeds to save will help us get good results and grow tomatoes that match the seeds we originally bought.
The Best Tomatoes to Save Seeds From
When saving tomato seeds, start with heirloom, heritage, or open-pollinated varieties. They include favorites such as Gardeners Delight and Black Krim, and the seeds from these plants will produce the same tomatoes as the parent plant. Keep this in mind if you’re shopping for seeds and hope to save seeds from your future harvests. Seed companies are pretty good about labeling tomato seeds with these terms.
If you save seeds from F1 hybrid varieties such as Sungold and Shirley, the resulting fruits may turn out completely different from the original. They might look wildly different or have an unexciting flavor. This can be disappointing after having invested so much time growing them, so try to avoid it if possible. I think that many beginners do save seeds from hybrids on their first attempt because they’re not aware of how plant breeding works.
You should also choose to save seeds from the best fruit you have from the healthiest plants. Avoid saving seeds from diseased or sad-looking specimens and never from unripe tomatoes. The seeds inside them aren’t mature enough to sprout. If you’re wondering what to do with your green tomatoes at the end of the season, green tomato chutney is the most delicious solution!
As an aside, if you want to grow F1 hybrid tomato plants from year to year, there is a way. You can propagate tomato plants from cuttings of your plants at the end of each summer. Overwinter them indoors or in another frost-free place and then plant them out the following spring. This clones the original plant and ensures the new one produces the same fruit.
Make Sure Your Tomato Variety is Self-Pollinating
Take a close look at a tomato flower. You will see a circle of yellow petals with a cone-shaped structure in the center. This cone comprises the male parts of the flower, including the anthers with their pollen. On most tomato plants, this cone completely encapsulates the female part of the flower, including the stigma, where pollination takes place. This ensures that only pollen from the flower’s own stamen reaches the stigma to fertilize the seeds. If plants self-pollinate this way, the next generation’s fruits will be the same as the parent plant.
Some tomato flowers have a similar arrangement, but the female part of the flower protrudes past the cone. It tends to be a greener color than the cone, and if you see it, it means that the flower can receive pollen from other varieties of tomato. So, if a bee lands on the flower, carrying pollen from another tomato type, the resulting fruits may differ from what you wanted.
You can save seeds from varieties with protruding stamens, but you may need to take extra measures to ensure that passing insects don’t pollinate them. You can do this by isolating the plant or placing a mesh bag over the flowers until they set fruit.
Method 1: Save Tomato Seeds on Paper Towels
Saving tomato seeds on paper towels is simple and the method that many of us prefer. It takes a few seconds, and the seeds stay stuck to the paper towel until sowing time. Then plant the seeds along with the paper, which eventually disintegrates. I tend to do this as I’m making canned crushed tomatoes.
Step 1
Cut open your chosen tomato and either squeeze or scoop out the seeds directly onto a dry paper towel. Spread them around with a spoon. Try to keep the seeds from touching, as this will make them harder to use later.
Step 2
Place the paper towel on top of another paper towel to soak up excess moisture. Leave the paper towels with the seeds on somewhere that will not be damaged by dampness.
Step 3
After a few days, you will find that your seeds have dried out, and the remaining pulp and gel surrounding the seeds have broken down. The seeds will also be stuck to the paper towel. Once your paper towel is completely dry, store it in a zip-lock bag or another container. When you come to sow your seeds the following year, cut out a square with a seed on it and sow, paper and all.
Method 2: Ferment Tomato Seeds
Fermentation is the most popular way to save tomato seeds. The fermentation process breaks down the gel coating on the seeds and separates the seeds from the pulp. Once rinsed and dried, the resulting seeds are clean and easy to store. This method also minimizes the risk of transferring diseases from generation to generation.
Step 1
Cut open your tomato, squeeze or scoop out the seeds, and place them in a glass jar.
Step 2
Add a small amount of water. Use roughly equal parts water to tomato pulp and seeds. Swill the contents of the jar around a little.
Step 3
Loosely cover the jar with a cloth or rest the lid on top. Allow some airflow into the jar, as the fermentation process needs air, but keep fruit flies out. Place the pot somewhere warm. This can be inside your house, perhaps on a warm windowsill or in an airing cupboard.
Step 4
After a few days, you can see the tomato seeds at the bottom of the jar. A few other things will float around in the water as the fermentation occurs, and it may smell bad. Add some water to the jar and stir or swill. Pour out most of the water, leaving the tomato seeds at the bottom of the jar. Repeat until the water is clear and you’ve removed the debris.
Step 5
When the water is clear, pour the seeds through a sieve or a strainer lined with a coffee filter. Rinse them under the tap, then spread them on a ceramic plate or waxed paper to dry. Once dry, store them in a small paper bag or another container to sow the next spring.
Method 3: Saving Tomato Seeds with Washing Soda
This method is detailed in the book Back Yard Seed Saving by Sue Strickland. It produces clean, easily stored seeds and works faster than fermentation. The seeds at the end are loose, dry, and easy to handle individually. They do come out a darker color than with the fermentation method, but they germinate just fine.
Step 1
Mix a solution of approximately one teaspoon of washing soda with one cup (250 ml) of water. First, use a small amount of very hot tap water to dissolve the washing soda, then top it up to the full amount with cold water. Aim for a solution at roughly room temperature.
Step 2
Cut open your tomato and squeeze or scoop the seeds into a jar. As with the fermentation method, cover the seeds in the jar with a small amount of the washing soda solution. Just enough to cover the seeds and swill them around.
Step 3
Lightly cover your jar with a cloth or place the lid on top, allowing airflow, just like the fermentation method. You can place your jar anywhere; it doesn’t need to be warm. So, if you have a cold house, this method might work better for you than fermentation.
Step 4
After just one day, you will find that the gel coating around the seeds has completely broken down, and the seeds have fallen to the bottom of the jar. You can then wash the seeds the same way we did with the fermentation method and let them dry fully. The seeds will likely appear slightly darker with this method, but this is normal.
Storing Saved Tomato Seeds
Once you’ve saved tomato seeds, store them in a dry, dark place at room temperature (68°F/20°C) or a little cooler. You can use moisture-absorbing packets to keep the seeds dry, and I tend to recycle the ones that come in product or food boxes for my seed storage boxes. Once saved, tomato seeds have excellent germination rates for the first six years. After that, germination trails off, but some should still sprout.
I hope these three ways to save tomato seeds have helped show how easy and satisfying seed saving can be. They will certainly save you a lot of money over the years, and the additional benefits are well worth the time you put into it. If you have any questions or comments, feel free to leave them below. You may also get an answer in the video I made showing how to save tomato seeds. Here are also a few more tomato ideas that might interest you, too: