Way longer than you likely think! Don't toss out those old seeds until you read this.
Seeds are miraculously resilient little life capsules that are meant to wait until the time is right for them to grow (moisture and temperature). However, seeds can get old and lose their viability. They may germinate more sporadically or not have enough energy to support germination and leaf development.
If seeds are not stored correctly they will be less likely to remain viable even to the end of their average life span. Be sure to keep your seeds in a storage bin with tight fitting lid and in a cool, dry location.
How Long Do Seeds Last?
On average, you can expect most vegetable seeds to have a life span of 3-5 years, however, there is a lot of variation so be sure to do some research an a germination test before tossing those seeds! Here's a great publication from Johnny's Seeds all about seed storage and average seed life.
Here's how to do a quick at-home germination test to see if your seeds are still viable!
Easy Seed Germination Test
One way to test your seeds for viability is a simple, at-home, seed germination test. Here's all you need:
Seeds (about 5-10 of the variety you are testing)
Plastic baggie or clear plastic to-go container
How To Test Your Seeds:
Wet the paper towels and lay it flat, folding it to be about the same size as your baggie or container
Put your seeds on one half of the wet paper towel and fold over the other half so that the seeds are covered (see lettuce seeds on wet paper towel above)
Place inside the baggie or container and seal
Label and date your baggie/container
Put in a warm place
Check daily for germination & adequate moisture
After your seeds start germinating, keep track of how many have germinated and when. If most have germinated by day three or four, it's likely that the rest are not as viable. You can calculate the germination percentage based on how many seeds you started and how many germinated. Seed packets are required to have the average germination rate listed on the packet.
If your seed germination was a success, you can then plant the seeds that germinated directly into your seed starting mix (for indoor seed starting) or potting soil (if starting outdoors).
Want to Learn More About Seeds and Seed Starting?
Check out this post about the benefits of indoor seed starting and some beginner tips! Or, contact me to learn more about garden consultations and coaching. I offer in-person or online garden coaching and consultations to help you learn how to grow!
Happy seed starting and garden planning. I hope to see you in a class or garden soon!
Together we grow! Marni