Tuesday, October 21, 2008

Saving Tomato Seeds

About a week ago I decided to eat the last Aussi tomato from my garden. This is a large beefsteak heirloom tomato. Yum. But I didn't want to eat it all. I wanted to save the seeds. Saving seed from heirloom tomatoes is relatively easy. Tomatoes are mostly self pollinating. The anther is hidden in the flower where the bees can't get to it (though I think there are a few weird ones out there). The pollen naturally falls to the stigma when the tomato plant is shaken by the wind or vibrated by the bees. So usually heirloom tomatoes breed true even if you have many other kinds growing right next to each other. The one caveat you must remember is that I say "mostly". They can occasionally surprise you.

Once you have the tomato, you take out the gel part that contains the seed. You put it in a small container, cover it and let it ferment in a warm spot for a couple of days, until a white disgusting slime grows on top. Did I do this? Not really. I did remove the gel. I put it in a small container and covered with saran wrap. I left it on my kitchen counter which I might point out is not very warm. In fact the thermostat in that part of the house is set at 62F degrees. Brrr. I let the containers be forgotten. Oops. A week later I remembered that they were shoved behind the squash. Yup one had that 'good' white mold on top, the other I think did at one point, but had dried out and a green mold had taken hold. Now if you let them sit wet for too long they can sprout on you. I didn't see any sprouting seeds. Hopefully they will be fine.

Then I filled the containers up with water and floated out all the icky mold. Most of the seeds stayed on the bottom. Once the seeds were clean, I put them out on some plates to dry. They need to dry for about a week or so. I think we are getting rain (I'm hoping since we have had no rain in three weeks), so it may take quite a while for them to dry. But at least I don't have an elementary school science project growing on my kitchen counter any more.

BTW I had two containers. The other one is from my Sungold tomato. This is an F1 hybrid. Seedman was saying that even if it is labeled F1 it might actually be a stabilized open pollinated plant. Or it might still be an F1 hybrid. If I have room next year I can play around and see what I end up with.


  1. Daphne, why the white mold step? Clearly I know nothing, becsuse I'd have just dried the little buggers. Which shows what I know.

    Hope yours do well come next season.

  2. It gets rid of the gel that the tomato seed is coated in. The gel supposedly contains something that inhibits the germination of the seed (so the seeds don't germinate inside the tomato as it grows).

  3. Interesting. I have never seen that green mold before though it looks like the stuff you get on bread? I don't use saran wrap when I'm fermenting tomato seeds just open containers. Somewhere else I real that too that some hybrids are actually just labelled so in order to entice a certain customer base. I look forward to seeing if they are okay next year.

  4. Great post. You can find detailed seed saving instructions for all the vegetables on the website of this 20 year-old non-profit dedicated to seed saving:


  5. Great post Daphne, I do save a lot of tomato seeds each year you know I'm a seed geek. LOL Tyra

  6. Excellent post. I had no idea one left tomato seeds to mold! I'll be veg seed saving next season, so this was a great lesson. Thanks.