If you’re like me, you’ve been collecting tomato seeds for the last several seasons. You might also be like me in that you enjoy growing new varieties every year.
This can lead to a build up of quite a variety of tomato seeds in your seed collection. But exactly how long are tomato seeds viable?
Tomato seeds are viable for an average of 4-6 years.
But that’s not a hard and fast rule. If you can keep them in a proper storage environment you might be able to sprout seeds that are many years older than that.
One thing to keep in mind is that over time the number of viable seeds in your stock will go down. So the older your seed is, the more you’ll need to plant just in case they don’t all sprout.
Of course, if they all do come up then you can share your bounty with friends or even sell the plants at the farmer’s market.
How long can you store tomato seeds?
The most important factor in determining how long your tomato seeds will last is the method in which you preserve them.
There are a few ways to save seed from tomatoes, and the method you choose can affect seed viability (hint: fermenting is the best).
The next thing that affects whether saved tomato seed will sprout is how you store them.
Seed that has been exposed to extreme temperatures, sunlight, and moisture are less likely to germinate.
Learn the best way to germinate tomato seeds here.
Do tomato seeds go bad?
Yes. For sure, tomato seeds can go bad. Most often this is due to moisture induced mold and exposure to extreme temperatures.
That being said, we’ve successfully germinated tomato seeds that are 7 to 10 years old.
If you want to grow 20 year old tomato seeds, I say go for it. I would pick through the seeds to eliminate any that are obviously misshapen, black, or moldy.
And I would plant extra (maybe even all the seeds you have) because you can bet good money that you won’t be getting 100% germination on 20 year old seeds.
How To Store Tomato Seeds Properly
The first step to storing tomato seeds properly is making sure they are completely dry before you put them into any storage container.
It usually takes about a week for tomato seeds to dry out, but a good rule of thumb is seeds that are easy to bend are still wet.
Dried seeds are very hard to bend or break.
Once you’re sure that the tomato seeds are dry, you just need a container to store them in.
Choosing where to store saved tomato seed
Paper envelopes, plastic baggies, and glass jars are popular options. If you choose a clear container, remember to place your seeds in a dark place as sunlight can affect their viability when it comes time to plant.
The next thing to consider is temperature. You can store seeds in the refrigerator or any air conditoned space.
Just make sure they’re not exposed to temperature extremes. So I don’t recommend you leave them in your car or garage.