Go grab a tomato and a small bowl of water. You and I are going to save tomato seeds. Because we are awesome. And cheap.
Giving tomato seeds away makes you, the giver, feel good because it allows you to selflessly pass on a solid 4 months of hornworms, a bit of crying and blight to a fellow gardener.
We gardeners are all about sharing. Except with the squirrels.
Of course the benefit is also that we, the seed saving people of the world, are all contributing to keeping these old varieties alive.
Nobody knows exactly how many varieties of tomatoes there are, but there are thousands. 3,000 of which are heirloom tomatoes. And THOSE are the seeds you want to save.
Table of Contents
What You Need
- ripe heirloom tomato
Quick Reference Instructions
- REMOVE THE SEEDS from a very ripe tomato into a small bowl.
- FERMENT THE SEEDS for 3-4 days by covering them with around ½ cup of water.
- STRAIN & RINSE the seeds in a sieve.
- LET THE SEEDS DRY by tapping them out onto a plate or bowl. It will take around a day for them to dry.
- LABEL & STORE your seeds in a paper envelope. Avoid airtight containers - if they aren't dried through, they can go mouldy in an airtight container.
What's an heirloom tomato?
An heirloom tomato is one that hasn't been bred with another tomato plant. Its genetics are always exactly the same as it's parent because tomatoes have both male and female plant parts and they pollinate themselves. Think of it this way - it's as if you had a baby and that baby was an exact replica of you. And when that baby grows up and has a baby it will be an exact replica of both of you. THAT's an heirloom tomato.
What's a hybrid tomato?
(hybrids are often labelled as an F1 hybrid on the seed packet or seedling)
So hybrids are more like actual humans. One variety of tomato is used as the "dad" and a different variety is used as the "mom". When those two breed together, you get a tomato has a combination of both parent's qualities. It will be unique.
Why do you need to know this? Because even though you can technically save seeds from any tomato, only an heirloom tomato seed will produce an exact replica of the tomato it was taken from.
Hybrid tomato seeds could produce almost anything but it won't be the same as the tomato you got it from or either one of its parents. You can still save these seeds, you just have no idea what you're going to end up with or if it will taste good.
So it makes sense that you're going to want to save seeds from heirloom tomatoes.
Having said that, I had a hybrid cherry tomato plant in my front garden years ago that self seeded itself. Ever since then I've let it continue to self seed. Some years the tomatoes taste fantastic, other years they're bland. But no matter what they climb all over my picket fence and look good.
Saving Tomato Seeds
Saving tomato seeds is easy but there is one crucial step you have to take that you don't do when saving other seeds like those from onions, flowers, beets or whatever else.
Tomato seeds need a period of fermenting (soaking in water until the water gets putrid basically). Strangely fermented pickles never get that same pukey smell.
You know that jelly-like guck around the tomato seeds? In order to remove that you need to ferment the seeds. Fermenting breaks down that guck that surrounds all tomato seeds.
- Cut a very ripe tomato in half across the middle (not from stem to blossom end) and scoop out the seeds into a small bowl. You can also just squeeze the seeds out.
2. The jelly-like guck surrounding tomato seeds needs to be fermented off by soaking them in water.
3. Cover seeds with water so they're submerged by an inch or two. Now you wait until a layer of mould appears on the top of the water and it starts to stink.
4. Let the seeds ferment like that on the kitchen counter for a few days. The first time you gag and think to yourself, There's definitely a dead raccoon in this kitchen - THAT'S when your seeds are ready for the next step.
5. Dump the seeds and putrid water into a sieve to drain and rinse.
6. Tap the cleaned seeds out onto a plate or bowl and label what type they are so you don't forget because you will.
To avoid any confusion or mix ups I write the variety directly on the bowl or plate with a Sharpie marker. It will just wipe away with a cloth later.
You can see that the pulp surrounding the seeds is completely gone.
Tomato Seeds Not Germinating?
Tomato seeds are pretty smart. They actually have a sprout inhibitor built into them so they don't start to grow while they're in the tomato.
Fermenting kills the sprout inhibitor and allows them to germinate once you plant them. Fermentation also protects the seed & makes it more resistant to disease and bacteria.
If you haven't fermented your tomato seeds before saving them your germination rate will be reduced because they still contain that natural sprout inhibitor.
No Tomatoes? No Problem.
Even if you didn't plant any heirloom tomatoes this year that doesn't mean you can't save seeds from them.
Take a trip to your local farmer's market or organic grocery store and buy a few heirloom tomatoes. Whatever looks good to you. Ask the farmer about them. They'll know which ones are the sweetest or saltiest. Take them home and taste them.
Save the seeds of the ones you like best.
HAHAHAHAHAHA. Just kidding. I know you, you'll save them all.
When to Save Them
The best time to save tomato seeds is at the beginning of the season when you have plenty of tomatoes. Or when you remember.
I usually remember in the fall after I've picked all of my tomatoes and the plants are just a crispy, brown, blight riddled vine clinging to the string I grow them on. So maybe go with the beginning of the season.
If you're reading this at the end of the season and your tomatoes are still green but a frost is closing in, DON'T LET THEM ROT & DIE A HUMILIATING DEATH ON THE VINE! Read my guide on how to save and store green tomatoes so they slowly ripen throughout the fall.
Not just because you're cheap. You're also vindictive. Those squirrels think the last tomatoes are theirs by default. Not this year Mr. Squirrel. Not this year.
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