How Long Are Tomato Seeds Good For?

Are you starting your tomato transplants from seed? Good for you! It’s the best way to control what you grow.

It’s the best way to access all the different varieties of tomatoes, too, so you’re not at the mercy of the few types the local garden center is selling.

When you do grow tomatoes from seed, there’s something you’ll want to know: Just how long tomato seeds are good for.

Jump to:

• Can I use tomato seeds from previous years for this year’s garden?
• I have more seeds than I need. What do I do with my extra tomato seeds?
• How long do tomato seeds stay good for?
• How to store extra tomato seeds:
• There’s no need to waste good tomato seeds!
• Tips for making the most of older and leftover tomato seeds:

Can I use tomato seeds from previous years for this year’s garden?

If you’ve grown tomatoes from seed before, there’s a good chance you have seed left over from a previous year. Can you use it?

Yes!

While there are some types of fruit and (more often) vegetable seeds that don’t last long and aren’t reliable from one year to the next, tomato seeds are not one of them. Tomato seeds will remain viable for several years, so yes, you certainly can plant last year’s seeds if you’ve still got them.

I have more seeds than I need. What do I do with my extra tomato seeds?

Conversely, if you’ve started this year’s tomatoes and you still have seed left, you can -- and should! -- save the extra for next year.

Saving leftover seeds from year to year is the best way to keep your gardening costs down. The most cost-effective thing you can do is to get as much out of every garden supply you buy. And that means seeds, too!

While it can feel like you should replace your seed afresh every year, that’s not the case. Seed companies don’t intend for you to buy new seeds when you have seeds from last year. In fact, many recommend using up your old seed first -- waste not, want not!

How long do tomato seeds stay good for?

Tomato seeds remain viable for a long time.

• Tomatoes remain viable for as long as 10 to 12 years, but that may be pushing it and is not the normal recommendation
• Three to four years is the most common recommendation for keeping and using tomato seeds, but five years is not unheard of either
• Plan on at least three good, strong years of viability for tomato seeds
• After three years, the older the seed is, the lower its germination rate will be
• However, if the seed sprouts, it’s good to go
• Low germination is the primary reason to replace tomato seed, but if it grows, there’s no reason the plant won’t thrive with good care!
• With good rotational storage and replacement practices, you should easily be able to keep seed fresh within a three-year time frame

How to store extra tomato seeds:

There are three keys to storing tomato seeds for use in future years:

1. Keep the seed dry
2. Keep the seed cool
3. Keep the seed dark

A good way to store tomato seeds (or any type of seed) is to store them in their original packets, in a covered box or tote. Plastic totes and photo storage boxes work very well.

If you have a desiccant packet (like the silica gel packs that come in shoes and dry items), throw a few in the box. That will help to protect the seeds from excess moisture or sneaky humidity.

Store your seeds in a cool closet or cupboard. Keep them away from a heater or heat source and away from appliances that generate heat (like refrigerator motors).

The kitchen and bathroom are not the best place to store seeds. Only keep them in the basement if it is not damp.

Often, under a bed or in a cool bedroom closet is the best spot for your stored seeds!

What about the tomato seeds I saved from my garden plants?

If you’ve saved your own tomato seed from heirloom varieties or open-pollinated tomatoes, there is no reason they won’t last for years, too.

There is nothing special about how commercial seed is saved or packaged. As long as you save and dry your tomato seeds properly, they should last three to five or more years, too.

There’s no need to waste good tomato seeds!

Seeds don’t expire, at least not for a long time.

You will find packing and sell by dates on all seed packets. These dates are not meant to be expiration dates.

Seed companies list these dates so that stores know what year the seeds were packed in. Stores need to replace the seed with new seed every year because they always need to be offering the freshest seed, but you don’t!

Seed packing dates are helpful because they can help you determine how old the seed is, but after that, you just need to see if the seed is still within the range of viability for tomatoes.

Tips for making the most of older and leftover tomato seeds:

• Write the date on all seed packets
• Use the oldest seeds first each year to maximize the economy
• If you don’t have enough leftover seeds for this year’s garden, buy just what you need to make up the difference, but still use last year’s seeds first
• You can always save extras from this year for next year
• Keep a rotation of planting that starts with the oldest seed each year, so nothing has to get aged out or go to waste
• Store extra seeds in a cool, dry space, protected from moisture
• If you’re not sure if your seeds are too old or if they will germinate poorly, there’s a simple germination test you can do here: home seed germination test
• It’s not a bad idea to start your saved seeds an extra week early. That way, if they don’t come up, there’s time to get a new seed and try again.