Learn how to save tomato seeds – it’s so easy! – and watch as your tomato plants improve year after year! And stored properly they will last you for several years to come!
We have a large vegetable garden, berry patch and fruit orchard that we keep going every year and one of the benefits of growing your own produce is that you can save the seeds to plant again the following year. No further seed purchasing necessary. Today we’re going to talk about how to save tomato seeds.
Harvesting and storing seeds for many plants is very straightforward: Simply gather the seeds, dry them and store them. Tomatoes however require a little more work.
What Makes Tomato Seeds Different From Other Seeds?
Tomato seeds are enclosed in a gel-like sack that contains growth inhibitors. These growth inhibitors prevent the seeds from sprouting inside the tomato, which is a brilliant mechanism in nature. The ripe tomatoes then fall off the tomato plants, land on the ground and begin to rot. This fermentation process removes the gel covering, the seeds sprout and new tomato plants grow. The challenge for those of us wanting to save the seeds to plant at some future date is that if the seeds are stored with the gel sacs intact, these growth inhibitors can decrease germination. And so the process of saving tomato seeds involves first having to remove those gel sacs by inducing fermentation.
From Which Kind of Tomatoes Can I Save Seeds?
Choose what are known as open-pollinated (OP) tomatoes, not hybrid varieties. Open-pollinated tomatoes include all heirloom varieties. Open-pollinated plants are more genetically diverse, meaning there is a greater amount of diversity among the plant populations. As you plant the seeds that you saved from open-pollinated varieties, those plants will slowly adapt to your specific growing conditions and climate and improve year after year.
When Should I Pick the Tomatoes for Saving Seeds?
Tomatoes reach seed maturity at the same time as maturity for eating, so pick the tomatoes when they are very ripe. Under-ripe tomatoes will reduce the germination rate.
How Long Do Tomato Seeds Have To Ferment?
It’s been a long-held belief that tomato seeds have to ferment to the point of developing a layer of mold on top of the liquid in the jar. Recent studies have actually shown that fermenting tomato seeds that long is not effective and can negatively impact germination. They concluded that seeds do best when they’re allowed to ferment for 1-2 days and that any longer than 3 days can have a negative impact on germination. If mold does develop on the top layer you can still proceed anyway, you may just have a slightly lower germination rate.
How To Save Tomato Seeds
Remove the Seeds: Select very ripe tomatoes and wash them. Slice the tomatoes in half and squeeze the seeds and juices into a glass jar. BE SURE TO LABEL THE JARS WITH THE VARIETY OF TOMATOES. If you have plenty of tomato juice in the jar with the seeds there is no need to add any extra water; otherwise add a little non-chlorinated water. Remove as many of the big chunks of pulp as you can. To prevent fruit flies or other things from falling into the jar, cover the jar with some cheesecloth or a napkin and rubber band.
Ferment the Seeds: Let the jars sit at room temperature (ideally between 70 to 80 degrees F) for 1-2 days to let them ferment (if the room temperature is cool it may take an extra day or two. Swish the seeds around in the jar a time or two each day. The seeds are ready when the top layer has begun to develop a very slight film on the top and the seeds have sunk to the bottom of the jar (don’t over-ferment; see section titled “How Long Do Seeds Have to Ferment?”).
Rinse the Seeds: Pour off the top layer along with the pulp and any seeds that have floated to the top. Pour the remaining liquid and the seeds at the bottom of the jar into a fine mesh strainer. Rinse the seeds thoroughly, swishing them around constantly to help remove as much of the remaining gel sacs as possible.
Dry the Seeds: Shake and tap the strainer a few times to remove excess water and dump the seeds onto a paper towel to remove more water. Do not let the seeds dry on the paper towels or they will stick to them. Immediately shake the seeds onto a tray or plate (paper plates work well or a tray lined with parchment paper) to dry. BE SURE TO LABEL THE JARS WITH THE VARIETY OF TOMATOES. Once they start to dry use your fingers to crumble the seeds each day to break them up and prevent them from clumping together.
How To Store Tomato Seeds
Scrape the seeds into paper envelopes or plastic ziplock bags. To ensure the seeds remain dry you can add a small packet of silica gel crystals. Store the seeds in a cool, dark, dry place. Refrigerating them is not necessary but that will ensure these conditions to enable your seeds to last the longest (that’s if you need them to last beyond a year or two). Do NOT store seeds in the crisper drawers in the fridge.
How Long Do Tomato Seeds Last?
If the process of saving and storing seeds is followed correctly, tomato seeds can last for 4 years, sometimes longer. People have reported successfully germinating tomato seeds after 10 years!
Do also have asparagus plants? Read our tutorial on How to Save Asparagus Seeds!