Saving tomato seeds isn’t terribly difficult, although it can get a wee bit on the aromatic side. Here are some tips on how to save tomato seeds.
Know Your Tomato Variety
The first thing is you need to know if the tomato variety you want to save the seeds from is a hybrid or open-pollinated.
A hybrid is a cross between two different tomato varieties. Seeds grown from the hybrid may or may not be like the plant from which they came. (Most likely they will be different.) Don’t save seeds from hybrids unless you want to be surprised!
If your tomato variety is open-pollinated (which includes heirlooms), then the plants you grow from the seeds you save will be just like the parent plant.
Saving Tomato Seeds
Here are the steps for saving tomato seeds.
- Pick the best examples of your ripe tomatoes (choose three or more tomatoes from each variety of the plants).
- Slice the tomatoes in half and squeeze the tomato juice and seeds into a small plastic container. Put only one tomato variety in each cup. Add a tablespoon of water.
- Label the container with the name of the tomato variety.
- Cover the cups loosely with plastic wrap and set them in a warm location (between 75 and 80 degrees is best). If it’s warm enough, you may want to set the cups outside because the next step can get, um, aromatic (smelly).
- Let the container set for at least three days; you will see white scum appearing on top of the liquid in the container. This is normal. And a bit strong-smelling. This is the fermentation process.
If the temperature is warm (around 80), let the container sit for another 2 or 3 days after the fermentation starts; if it’s been cooler, you may need 4 or 5 days. Then you’re ready to clean the tomato seeds.
Here’s how to clean out the containers and get the seeds. (Hint: do this outside if you can.)
- Grab a pail and either a garden hose with a pistol-grip sprayer or several small bottles of water. Add some water to the container with the seeds and swish it around some. The good seeds will fall to the bottom; bad seeds will float to the top.
- Dump out as much liquid as you can, along with the bad seeds, then add some more water and swish again. Dump out the excess water.
- Repeat until the water is clear, which means the seeds are clean.
- Grab a paper towel and dump the seeds onto it, to absorb any extra moisture, then transfer to a paper plate.
- Spread the seeds around on the paper plate so they aren’t piled up; they need to air dry. Label the paper plate with the tomato variety name.
- Move around the seeds once a day to make sure all sides are sufficiently dried. They should be good after two or three days, unless you have the paper plate with seeds in a humid location. If that’s the case, give it a few extra days.
- Store the seeds in a paper envelope, small plastic bag or a small container with a lid. Label your container!
Place the seeds in a cool, dry place and they should last several years (although they are best used within 2 to 3 years if possible). However, I have seeds over 10 years old that are germinating fine, even as I write this. Still, the sooner you use (or share) the seeds, the more likely they are to germinate and thrive.