Harvesting your own tomato seeds

September 04, 2024

Fermenting seeds is, in my opinion, the easiest way to clean and store tomato seeds. The principle is simple. In tomato seeds, there is a so-called seed bag, a jelly-like casing that protects the seed from germination and other external influences.

By fermenting the seeds, you ensure that you naturally break down the seed bag and can then store the seeds longer and better.

Did you know?

Fermentation is of course not only applicable when extracting tomato seeds.It can be a way of preparing food, it is also used to make alcohol, and it is primarily a way to break down biological materials with the help of molds and bacteria.

What do you need?

A small jar, a glass or cup (one variety per jar)
Your favorite tomato or the tomato from which you want to win seeds
A small knife
A teaspoon
A (sticky) label on which you write the name of the variety

How do you harvest tomato seeds?

Take the fruit and make sure all your material is ready, it works faster and easier.
Take a jar and halve the tomato (you can also push out cherry types by hand, large fruits are better hollowed out with a spoon).
Remove the tomato seeds with a teaspoon and put them in the jar.
Then fill the jar with a little bit of water. Fermentation only works if there is enough moisture present.

Stick on the jar a label with the name of the variety, along with the date you harvested the tomato seeds.
Place the jars where they won't bother anyone. I've been putting them in the garage or in a sheltered spot outside for years and it works fine. If you don't mind a few dirty, mouldy jars, feel free to put them in a corner in the kitchen. It's often warmer there, which speeds up the fermentation process a bit.
After an average of three to four days, the process is complete - depending on where you put them and how warm it is there.The warmer it is, the faster the tomato seeds will mold; the colder it is, the longer it takes.
Get a clean sieve ready and make sure the jar with tomato seeds is prepared.
Add water to the jar with a strong stream and wait until the tomato seeds have sunk to the bottom. High-quality tomato seeds will sink, while impurities, dirt residues, and poor tomato seeds will float on the water surface.
Scoop out all the dirt residues and mold with a spoon.
Put the tomato seeds in the sieve and rinse well.
Place the tomato seeds on a dish and spread them out with your index finger.
Let the tomato seeds dry at room temperature and make sure to label the variety name and date again on a label and stick it on the dish.
After a week, rub the tomato seeds loose and let them dry for another week.In theory, it can be done faster, but I want the seeds to be completely dry before they are packaged.
Package the tomato seeds in bags. Don't forget to mention the name of the variety and the date.

Seed extraction without fermentation

Another way to extract seeds from tomatoes is to lay the seeds on an absorbent cloth or kitchen paper and package them dry two weeks later. In my opinion, this is not the best way. The seed bag is dry but not gone, the germination power decreases and the seeds are noticeably less long-lasting.