How Long Do Seeds Last?

How to Know If Those Seeds Are Still Good

February 8, 2021
Seed Catalogs
Robin Sweetser

How long do garden seeds last? How do you tell if your old seeds are still good? Let’s find out!

Wintertime is the season when these questions matter. The gorgeous seed catalogs arrive in the mail, tempting you with beautiful photographs.

But before you go crazy, it’s time to inventory your leftover seeds to avoid duplication and determine viability.


How Long Do Seeds Last?

Some seeds have a longer life expectancy than others. Most last for a couple of years if stored in a dry, cool place.

  • I have learned from experience that onion seeds are not much good after the first year, but tomato, cucumber, and melon seeds can last 5 years or more.
  • Brassicas and squash seeds are good for 4 to 5 years.
  • Parsley, sweet corn, leeks, parsnips, shallots, and chives require fresh seeds every year.

Seeds are living things and their viability is affected greatly by the way they are stored. Most experts agree on dark, cool, and dry conditions as being the best. We keep some of our seeds in the refrigerator, but most are in open boxes in the dining room—probably not the best location.

How to Tell If Your Seeds Are Still Good

If I have a question about the viability of some seeds—such as those beans that someone gave me back in 2012—I will test a few.

This is as easy as placing ten seeds on a damp paper towel, folding it up, and placing it in a plastic bag. Put the bag in a warm spot and check after a week or so to see if any of the seeds have sprouted.


  • If 2 out of 10 germinate, that means a germination rate of about 20%—not too good, so I would either plant more of them than usual or buy fresh seeds altogether.
  • If 8 out of 10 germinate, that means 80%—not bad at all, and I can likely get away with using them for another season.

Once you have determined what you need, you can shop with a clear plan in mind and be less likely to overbuy.

Have fun looking through this year’s seed catalogs and dreaming of your best garden ever. Summer is just a page away in a seed catalog!

Speaking of which, check out our list of free garden catalogs and sites.

About This Blog

Get inspired by Robin Sweetser’s backyard gardening tips and tricks. Robin has been a contributor to The Old Farmer’s Almanac and the All-Seasons Garden Guide for many years. She and her partner Tom have a small greenhouse business and also sell plants, cut flowers, and vegetables at their local Farmer’s Market.