How to Test Old Seeds

A Simple Seed Viability Test

How to Test Old Seeds. Photo © Erin Huffstetler

Have old seeds, and not sure if they're worth planting? Do a simple viability test to find out.

Difficulty: Easy

Time Required: Varies

Here's How

  1. Lightly moisten a paper towel. Then, fold it in half.
  2. Place 10 seeds on the paper towel. Then, fold the towel in half again to cover up the seeds.
  3. Stick the paper towel in a plastic sandwich bag and seal.
  4. Write the seed name and date on the bag. Then, store the bag in a warm spot (on top of the refrigerator works well).
  1. Check the bag each day to see if any seeds have germinated and to remoisten the paper towel, as needed.
  2. Continue checking the bag until you reach the germination time listed on your seed packet.
  3. Count how many seeds germinated. Use this to determine your percentage of viability. If, for example, 8 of your 10 seeds germinated, that would be an 80% viability.
  4. If you decide to use your seeds, plant extra to make up for the seeds that aren't likely to germinate.


  1. If you handle them gingerly, your germinated seeds can be planted.
  2. Need to replace your seeds? Here's how to get free seeds
  3. Use this seed starting printable to track the success of your indoor seed starts

What You Need

  • Seeds
  • A paper towel
  • A plastic sandwich bag
  • A permanent marker
  • Water