Before you order more seed packets for your 2025 garden, check your stash. You may have plenty of seeds that will grow just as well this year as they did in 2024.

All seed packets are marked with a “packed for” date stamped on the packet. Seeds in the garden center now will say “packed for 2025.” Garden centers have to remove all seeds packed for the previous year at the end of the garden season. However, that date is not an expiration date and most seeds will still be viable for several years after the year they were packed for.

How long seeds last depends on the seed type and how it was stored.

Long Lasting Seeds

Under ideal conditions, many seeds will remain viable a decade or more. Most likely, your basement is not ideal. Seeds for vegetables such as onions, spinach, parsnips or parsley should probably be used the first year you buy them. However, seeds for watermelons, winter squash, tomatoes and radishes will still germinate after several years. Among flowers, seeds for tropical milkweed, impatiens and violas are not long-lasting, whereas those for zinnias, cosmos and nasturtiums will last for years. Here’s a good chart with typical seed viability for different crops.

Seed Storage Tips

No matter the seed, they are best stored in an environment that is cool, dry and dark. I store my seeds in a lower-level storage room where the air is fairly chilly and dry and the lights are rarely turned on. You can keep seeds in the envelopes they came in and store the envelopes in an air-tight container, such as a mason jar or a plastic bin. If you have leftover silica packets from shoes, purses or medicine bottles, throw one in. They will help keep the air dry.

Be sure the seeds are labeled properly, and if you have a lot of seeds you’re saving from year to year, you may want to come up with an organization method as well. Seed boxes or binders work well for storing and organizing seeds.

Testing for Viability

If you are not sure if a seed packet is viable, it’s easy to test for germination. Simply wet a paper towel and wrap a few seeds in it. Put the damp paper towel into a zip lock plastic bag and set aside. Check how long the seeds are supposed to take to germinate. After that time, open the bag and check for germination. If a significant number of seeds have germinated on the test, you are OK to plant the seeds this year.

Whether you buy seeds or save them from year to year, check out our posts on seed starting techniques.

Mary Lahr Schier is the author of The Northern Gardener: From Apples to Zinnias.