Tomatoes for next year

I have a bunch of ripe tomatoes that I want to save the seeds from (they were volunteer from the year before and taste wonderful.)  How do I go about saving them for next spring? Is there a set of conditions I need to meet - to wet/dry etc?

Pick tomatoes from plants that did best in your garden.  You want seeds from as many of your best plants as possible each year.  Then cut each tomato open and pull out a few seeds from each.  Place seeds on paper (we use wax paper), to dry.  Once the seeds have dried, place them in a cool dry dark storage place in an envelope.

I ferment mine. I cut at the equator and scoop the seeds into a open container. Most of the tomato, minus the seeds still gets eaten. Then I check the container of seeds daily until the gel sac is broken down a bit. Then I use a fine wire mesh strainer and the sprayer on the kitchen sink to rinse. Spread them on a plate, air dry, crumble, and into an seed packet or envelope.

Also, tomato seed is long lived. So you can keep seed from older years as backup. That cuts down on the need to collect from multiple plants. Best plants sometimes end up being natural hybrids.

I've only ever spread tomato seeds on a paper towel and let them dry. Label the year and characteristics you liked right on the paper towel. I just fold the paper towels up and shove them into a paper bag that's tacked to the wall.

It's pretty humid here, so we have to be mindful of storing the seeds in a dry place with airflow. That's why I tack them to the wall, high up, and away from the sink.

I just tear off a seed and plant with the bit of paper towel stuck to it. I've never had the time or patience to ferment tomato seeds and never had a problem with germination, but it's up to you the method that works for you.

It partly depends on what you want to do with the seeds and partly on what you want from them.

If you wanted to trade tomato seeds, have seed bourne pathogens, or wanted to use a seeding machine, then fermentation or even further steps like heat or chemical seed cleaning might be needed.

If you simply want a few seeds for your own use, the paper towel method works.

Richard Clemence a Ruth Stout coauthor had a technique where he buried a few tomatoes next to a stake in his Ruth Stout style hay mulch each fall. Then dug up and planted the seeds in the spring. They never left the garden.

I do a lot of direct seeding with a garden seeder. I find intentionally planted seeds always outperform volunteers in terms of germination in my garden. I think the stake and mulch method could be an improvement over random volunteer germination. Though I haven't tried it and don't trust my rodents not to redistribute the seeds.

I also do some trading. So I ferment. Fermenting reduces some pathogens. I've watched YouTube videos of heat treatment which is a better pathogen removal tool, but is more advanced than I need. I've  read about an entirely chemical means to clean the gel off the seeds but never tried it.

For trading or selling, cleaner is better.

It sure doesn't need to be complicated though. The tomatoes in question volunteered this year, with luck or maybe a little help from a stake or a little strip of paper towel there is a good chance they will be back next year.