At about this time of year (or sooner) you may be thinking about what you’ll be growing next year, especially if one or more varieties of tomatoes were particularly successful. You can, of course, just buy new seeds every year, but if you are growing an unusual variety, you may want to consider saving seeds from the most vigorous plants. In our case, we grew some really successful varieties bred at the University of Florida, and they specifically suggested that we save their seeds, since they’d rather not be in the commercial seed business.
You can save seeds from any variety, but you will have the best results from ones that are open pollinated, meaning that the seeds will produce the same variety of plant as the parent. This may not be true of hybrid varieties and saving them is a bit riskier: you can’t be sure their progeny will be the same as the parent plant.
Some writers suggest only saving “heirloom” seeds, but this is probably a bit extreme. Heirloom really means that most growers have gone on to something better than that variety. Heirlooms may have lower yields and be less disease resistant. There are still plenty of great tomatoes you can save seeds from, such as Better Boy, for example.
You want to pick a good example of the fruit to take seeds from, but it needn’t be perfect. The tomato could be cracked or have a recent slug or fruit borer hole, as long as it hasn’t rotted.
The difficulty in saving tomato seeds is that they are enclosed in slippery little gelatinous sacs, that are hard to work with. And that gel sac also includes a growth inhibitor, so the seeds won’t sprout within the plant. You need to remove that as well. We’ll show here how to overcome that problem below.
(Seeds do sometimes sprout inside a tomato, which is a kind of a surprise, but is usually harmless. It’s called ovipary.)
Saving the seeds
Cut the tomato in half and scoop out some seeds and the accompanying sacs. We used a melon baller, but a spoon would also work. Put the seeds in a fine strainer and rinse them with running water. We used the sprayer setting on our kitchen faucet to try to blast open the little sacs. This works to some extent, but we found that alone this wasn’t enough. Those seeds neve germinated.
The next step, recommended by a number of writers is to use Oxyclean stain remover. Put some tap water into a glass or pitcher and add a tablespoon of Oxyclean powder. Stir it in, and then add the seeds, including the gel and any bits of tomato that have seeds attached.
Let them soak in the mixture of half an hour. During this time, the seeds will probably float to the surface. Then pour the seeds and some of the solution through the strainer again and rinse the seeds using running water. Pick out any bits of tomato that end up in the strainer.
Finally, prepare a paper plate with a napkin or coffee filter on it to catch the seeds, and dump the seeds onto that tissue. Incidentally, seeds may stick to a napkin, and parchment paper is better, but of course, it doesn’t absorb much water. Label the plate with the tomato variety and let the seeds dry on the plate for 1-2 weeks.
After that, put the seeds in envelopes and label the envelopes. Put the seeds in a zip lock bag and keep them in a cool, dry place. You can even store them in the refrigerator or freezer according to the Florida research group.
Testing the seeds
You might want to test the seeds to make sure they will germinate. To do this, put two or three seeds in a damp paper towel, and enclose it in a zip lock bag. The seeds will sprout in around 10 days.
Then you know you are ready for the next season!