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Tips on how to easily save tomato seeds on a paper towel and tips on sowing them the following year. This method is the best way to save tomato seeds and you can store and plant the seeds very easily.
Saving tomato seeds is extremely easy and a great way to save money and regrow your favorite varieties. However, some make out that saving tomato seeds is more complicated than it needs to be. That you need to ferment them and go through a days-long process of filtering, drying, and storing. You really don’t need to do this at all, though. Saving tomato seeds on paper towels is really the way to go for the home grower and will save you much time and effort.
Use these tips to save seeds from your favorite open-pollinated tomato varieties. It will take you all of a few minutes, plus drying time, and the seeds can be viable for up to fifteen years stored this way. You can also plant the tomato seeds still on the paper when it comes to growing tomatoes in spring!
Open-Pollinated Varieties vs Hybrids.
Firstly, a word of caution on saving vegetable seeds of any kind. If they’re not open-pollinated then the plants that grow from the seeds will probably not grow true to the parent plant. Many of the seeds available to the home grower are F1 hybrids which can be more vigorous but will not grow true from saved seeds. These are perfectly fine to grow and eat and not in any way genetically modified (in the modern sense), but you should avoid trying to save seeds from them.
F1 hybrid seeds are the result of breeding two different varieties that produce consistent offspring with good yield. That offspring is the F1 hybrid plant growing in your garden! If you save seeds from the fruit of that plant, they probably won’t grow plants that produce the same kind of fruit.
Seeds saved from open-pollinated varieties can grow true, though, as long as they haven’t cross-pollinated with another plant. More on that is below. So if you’re looking to save tomato seeds, avoid saving seeds from tomatoes that are F1 hybrids and stick with heirloom varieties that are open-pollinated.
Cross-Pollination of Tomatoes
Cross-pollination can be a big headache for the home seed saver. What happens is that wind and bees and other insects spread pollen from one flower to another. When this happens it shares genetic material from one plant to another and can stimulate a flower to become a fruit. Usually, when this happens, the cross-pollinated crop doesn’t look any different from a crop that isn’t cross-pollinated. It’s the seeds inside the fruit that carry the genetic cross though.
For example, if squash is growing next to a zucchini, bees can spread the pollen from one to the other. You wouldn’t know it from the crops that season though because the zucchini looks and tastes just like zucchini and the squash looks and tastes just like the squash variety you planted. But if you save the seeds from either, and grow them the next year, your plants will be a cross of both squash and zucchini!
Fortunately, tomatoes do not cross-pollinate with one another that easily. They’re self-fertile and usually pollinate themselves before the flowers have a chance to open. That means that saving tomato seeds is much safer than other types of vegetables that cross-pollinate more readily.
Saving Tomato Seeds by Fermenting
The most common method of saving tomato seeds that you’ll see recommended involves fermenting them. You scrape tomato innards into a jar, add water, and let the whole thing start fermenting and even molding over. Then you strain, rinse, and dry the seeds.
This is the way that seed companies clean and save tomato seeds and it’s a good method. It removes the gelatinous covering around the seed and makes the seeds easy to sort into little sachets to sell. However, this is not the easiest or, in my opinion, the best way to save tomato seeds for the home grower.
Save Tomato Seeds on a Paper Towel
For me, the easiest way to save tomato seeds is to scrape them out of the fruit and on a paper towel. Afterward, I spread the seeds and pulp out. This creates space for the eventual seedlings to grow and helps speed up the drying time. Then I let the seeds dry completely then fold the paper up and store it in an envelope or ziplock bag. I usually write the variety and year directly on the paper towel.
Saving tomato seeds in this way also makes them easy to share among friends. The seeds stick to the paper and are held there, completely viable, for up to fifteen years. I learned this technique from a friend who sent me some of his ‘Late Plum’ variety.
Growing Tomato Seeds Saved on Paper Towels
When the time comes to grow the tomato seeds, use a pair of scissors and cut a square off the paper towel. Save some of the seeds for another spring. Then plant the whole piece of paper in compost, covering it just lightly. The seedlings will grow just fine, paper and all. It will eventually degrade into the soil but even if there’s some left when it comes time to trasplant, it will tear away easily. You’ll want to transplant your seedlings into individual modules when two true leaves have appeared.
Sow Tomato Seeds in Late Winter to Spring
Growing tomato plants from seed isn’t difficult but it’s best to start them early if your springs are cold. On the Isle of Man (Coastal zone 8), it’s practically impossible to grow them outdoors early in the year. If you’re in a similar climate, nurturing them in a greenhouse, polytunnel, or warm windows is the best way to go forward. Use tips for starting seeds indoors to get a head start on spring.
For me, growing tomatoes begins in mid-February when I sow the seeds for my greenhouse and polytunnel-grown plants. If you’re in the same climate as me but will be planting into unheated greenhouses, wait a couple of months later.
Grow Tomato Seeds on Paper Towels
To start your seeds this early you’ll need to do it in a warm place with plenty of light. Bottom heat is preferable and if you don’t have a propagator then setting the tray of seeds near a radiator works well too — just make sure it isn’t too hot and that the compost stays moist. Popping the tray into a clear plastic bag also helps in both retaining heat and moisture.
Use multipurpose or seed-starting compost and the rule of thumb in sowing is to cover the seeds with soil twice the depth of the seed itself. So if the seed is 3mm in length (the size of a tomato seed) then cover it with 6mm of soil.
Sprinkling a light layer of horticultural grit on top helps the compost retain moisture and won’t bother the seedlings at all. Tomato seeds germinate best at around 70-80°F and at this temperature you can expect to see green shoots within 6-8 days. When the sprouts have developed two true leaves it’s time to prick out tomato seedlings.
Propagating tomato plants from cuttings
If you’re growing a tomato plant, heirloom, or even an F1 hybrid there IS another way to keep the plant going year after year. This way is a little more involved but the plants you create will be far ahead of any that you grow from seed. If you’re intrigued, here’s how to propagate tomato plants from cuttings.