Small scale tomato seed processing - question

Do you guys all prepare tomato seeds only by the fermentation method? For single tomatoes from crossed flowers, I’m wondering if it’s ok to just wipe the jelly off the seeds then rinse them in water? I seem to be able to get them very clean this way - its easy to get the jelly off by rubbing the fresh seeds with kitchen paper, then I rinse them in a sieve just in case any sugars might lead to mould - and I can’t think of why this is not a good idea. It means I can give my full attention to the few seeds from individual tomatoes, and the process is speedy, and gives less chance for accidental neglect or mixing anything up, plus saving a lot of space.

Has anyone tried this? Or can think of why this might not be a good idea? Here’s a photo of some I just did this way today:

This could also have the benefit perhaps, of saving the endophytes? In the endophyte course the … professor?.. did warn against the fermentation method for that reason, though offered no alternative. I had the sense his knowledge was more theoretical than practical, but anyway, curious what other people think of this method. I would hate to loose a cross by over-fermenting seeds, and with so much going on, that is a definite possibility. And when it comes to pimpinelifolium for example, having to ferment, and keep track of, individual fruits, would seem an awful lot of work for such a tiny fruit! Same for other wild species.

Oh and… I did actually do this (minus the rinsing) with some seeds of one plant over winter but I lost the 2 seedlings, likely for other reasons. So I have no proper test of this method yet, but for sure the seeds saved for a short while germinated fine at least.


I ferment if I have enough seeds and associated gloop. If not, I clean them pretty much as you describe your cleaning of a few seeds. It’s worked well for me over the last 20 years or so.


Ok thanks @RayS , that’s very reassuring to hear!

I have used sieve and spoon to break the jelly, then use water to separete flesh in a container as it will come first when I pour it. Then just repeat. Also you can first pour jelly out, then pour seeds with jelly to sieve and at the bottom there should be fairly clean seeds. Slight downside is that some seeds might shoot out when pressing with spoon, but that’s not problem if you have more than just few F1s. I have used same for bigger amounts but now thinking of some other (or improved) method (besides fermenting) to separate thousands of seeds as using this method takes time for bigger amounts. Been thinking of some gentle blender (maybe salad drier would work?) that could break jelly of and then separate with water as before.

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I think fermentation is very helpful for large amounts of seeds because removing the jell greatly reduces how badly they stick together when drying, makes them dry faster and prevents mold.

For small amounts like in your photo your method sounds like a fine way to do it. I might still wash them though just to remove excess. I do that, fermented or not by putting them in a sealed bottle shaking it up good and pouring off the guck. Then dump the last rinse with the seeds into a strainer. Once they are clean, I dry them on a non-stick surface such as a glass plate rather on paper or cloth.

I don’t worry about endophytes; I figure if they are there then they are in the soil too so no need to preserve them on the seeds.

Ah yeah I forgot to mention the step I do before all this - I get the bigger parts off in my mouth :slight_smile: But doing that shaking thing might be a good idea, today’s was not actually crossed, I just wanted to eat the tomato and save some of the seeds by spitting them out, then doing the steps I mentioned. When every seed is precious, I’ll perhaps try that step you just recommended. And I’ll think about drying them on glass maybe too, thanks. Although on paper with small quantity, I pad them down then move them slightly so they don’t tend to be hard to get off the paper.

Ha ha, goes against the spirit of the endophyte course somewhat! And might make a difference if sharing seeds with others. Then again though, I’d assume they’re adapted to travelling through the digestive system so I was never totally convinced that the fermentation method worsens them. But since it was on the endophyte course, I remain with an open mind about it. Would be nice to see it tested one day. But for sure here my main concern is just making sure to do my best to take care of crossed seeds without killing or loosing them, so, I’m glad my method should be fine for now, by the sounds of it.

After taking the endophyte course, I skipped the fermentation process last year and just spread out the tomato seeds to dry on a paper towel, sprinkled with a little chicken compost. I didn’t even bother getting rid of the goo. Seemed to work fine, got good germination this spring.


I don’t ferment. Just a strainer and running water. The point is to get the growth inhibitors (the gel) off, which would otherwise rot off during a winter in the ground. It’s there to make sure the seeds don’t sprout too early in a natural setting.

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For me, fermenting is the easiest method and I mostly do that. I leave them for a couple of day, then rinse and dry them.
Last year after taking the endophytes course I have both fermented and not fermented seeds of 9 varieties of tomatoes. The seeds left alone germinated slower, but in similar rate (over 90% for both).


It will be wonderful if you can keep them labelled and grow them in similar conditions, and keep track of how they do over the season! I hope you share that here so we can see how it goes!

Hi Justin, for now, these tomatoes finished their seedling stage and have been planted outdoors a few days ago. So far, no visible difference. We will see how it goes.

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I always ferment. Even when it is just a couple seeds. I wash little single serving yogurt cartons and use them for my small ferments. When I do a really big ferment sometimes I use a five gallon bucket. I’ve never saved enough tomato seeds of something to need a larger container than that! One of my tomato friends used to just stick them to paper, dry them out, cut it up, and mail little pieces to people. Still have some like that.

Why? I mean, is there a reason I should know? Some people are saying it’s important.

Meaning just straight from the fruit without fermentation?

I read the book seed to seed many years ago and that is how I learned. I’ve just stuck with it.

My friend who doesn’t or didn’t learned the stick em to paper method.

For seed swapping or seed selling it is handy to ferment. Fermented, rinsed, dried, crumbled, sieved, and blowed and you get nice looking easy to handle seeds ready to sell.

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As far as the course I look at such things sort of like Captain Barbosa said of the pirate code, “is more what you’d call guidelines, than actual rules”. For sharing I would rather risk leaving out the possibility of sending something good and also the reduce the possibility of sending something nasty.

No chemicals of any kind, no adherence to the code of garden housekeeping, compost that doesn’t get hot enough to kill anything, for decades. My garden grows very well as a rule, everybody gets along, but who knows what might happen if some of my microbes ended up in a garden with plants that weren’t accustomed to them.

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All sounds good. Regarding this last part, not arguing for not fermenting, but just saying, I think this is a most significant reason for breeding genetically diverse crops.

I’ve always had faster germination and faster growth with fermentation in tomatoes. I’ve tried both ways multiple times.

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I have totally done this for the last 12 years or so. Just recently learned about the whole fermenting seeds thing. Actually in somemcases I would just scrape the goop off a cutting board (from making a tomato salad or some such) and spread the seed out on paper towels, once they dry I could easily peel them off, goop would stay behind. Or I would just label the paper towel with a ballpoint pen and fold the whole (very dry) thing up to store until next year. Perhaps not very professional, but I have never had a problem with germination or anything.

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I am always worried they would dry on and get stuck, but perhaps that’s because I think pf them and their goop as a unit :woman_facepalming:t2::laughing:

I clean them first so there doesn’t seem to be a sticking issue, but if a tiny bit of paper comes away with them, I think that’s no big deal anyway. It’s just wood fibre!

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