I don’t collect hybrid tomato seeds as they may not grow back true.What that means is they may revert back to one parent or the other that they were crossed with. Heirloom tomatoes will grow back true.
The only heirloom tomato seeds I collect are from my giant tomatoes as I’m trying to get some seeds that do well in our high desert and give me some big, really big tomatoes. Last year I got 3 tomato seeds from a giant grower who grew a tomato over 7 lbs in Ohio. This year I got a pretty large tomato from one of those seeds. I kept the tomato which measured 19 inches in diameter and almost weighed 3 lbs and recently got the seeds. I will try some of these seeds next year as well as other big tomato seeds that I got from another grower this week. Here’s how you can collect your favorite heirloom tomato seeds.
To collect tomato seeds, cut the tomato open, squeeze and scrape out all the seeds and put them in a little jar with some water. Then put the lid on. Try to not get too much pulp in with them. The seed/water mixture will start to ferment in a couple of days and it might bubble a little which is good. The fermentation will remove the slime on the seeds and the seeds will fall to the bottom of the mixture. When almost all the seeds are on the bottom, pour out the liquid, seeds and pulp through a fine sieve, removing the pulp. Keep rinsing until only the seeds are left. Spread them out on a paper towel to drain the excess water and then put them on another paper towel to finish drying. Before the seeds dry completely I move them around so the paper doesn’t stick to them. After they are thoroughly dry, put them in a ziplock baggie, label and store. You can keep any heirloom tomato seeds this way.
My only concern with collecting tomato seeds is if you plant cherry tomatoes too close to the heirloom tomato you want to keep, they may cross-pollinate so think about where they will be in your garden next spring and don’t plant them right next to each other. Tomatoes aren’t pollinated by bees but by the breeze or are self pollinating. Tomatoes originally came from South America and honeybees came from Europe or Africa so tomatoes aren’t native plants to the honeybee hence they aren’t interested which actually makes pollination easier to control.