How To Check If Your Seeds Are Still Good To Plant

Seed viability tests are essential for any gardener who wants to ensure crop success. The viability of seeds determines their ability to germinate and grow into healthy plants. Planting non-viable seeds can result in wasted effort and resources.

Seed Germination Tests

It’s important to test the viability of seeds before planting them because depending on how they are stored, seeds have a limited shelf life. In this article, we will explore two simple and effective methods for testing seed viability: the paper towel test and the soil test.

These tests are easy to perform and require only a few basic materials, making them accessible to gardeners of all levels of experience and will give you the knowledge and tools to confidently test the viability of your seeds and optimize your chances of success in your gardening endeavors.


The Paper Towel Test For Seed Viability

The paper towel test is a simple and effective way to test the viability of seeds and to monitor their germination progress. To perform the paper towel test, you will need the following materials:

  • Paper towels or coffee filters
  • A sealable plastic bag
  • Seeds
  • Water

Here are the steps to follow:

  1. Take a few sheets of paper towels or coffee filters and moisten them with water. Make sure the paper towels are damp, but not soaking wet.
  2. Spread the moistened paper towels on a flat surface.
  3. Place the seeds on the paper towels, spacing them out evenly. Make sure each seed has enough room to germinate and grow.
  4. Fold the paper towels over the seeds to cover them completely.
  5. Carefully transfer the folded paper towels with the seeds into a sealable plastic bag.
  6. Seal the bag, leaving some air inside to create a moist environment for the seeds.
  7. Place the plastic bag in a warm and dark location, such as a closet or cabinet. (Note: There are a few seed types that require light to germinate – see table below.)
  8. Check the seeds daily to monitor their progress. After a few days, you should start to see some germination activity.
  9. Keep the paper towels moist throughout the germination process. You can add a few drops of water if necessary.
  10. After a week or so, remove the paper towels from the bag and carefully examine the seeds. The ones that have germinated should have small roots and shoots. Count the number of seeds that have germinated and calculate the germination rate.

The paper towel test is a great way to test the viability of seeds before planting them. It allows you to identify seeds that are unlikely to germinate and to avoid wasting time and resources on non-viable seeds.


Soil Test For Seed Viability

Some seeds when tested for viability will be better performed in soil rather than using the paper towel method. One reason for this is the presence of Potassium Nitrate, which some seeds need to germinate better. A few seed varieties that do better in soil are brassicas, eggplant, peppers, tomatoes, basil, endive, radicchio, and most flower seed.

Soil Test Seeds

To perform a soil test for seed viability, you will need the following materials:

  • A container with a lid (such as a plastic cup or a mason jar)
  • Soil
  • Water
  • Seeds

Here are the steps to follow:

  1. Fill the container with soil, leaving some space at the top.
  2. Add water to the soil until it is moist but not soaking wet.
  3. Plant a few seeds in the soil according to the recommended depth and spacing for the type of seed you are testing.
  4. Label the container with the name of the seed and the date of planting.
  5. Close the container with the lid and place it in a warm and dark location, such as a closet or cabinet. (Note: There are a few seed types that require light to germinate- see table below.)
  6. Check the container daily to monitor the progress of the seeds. Keep the soil moist but not soaking wet.
  7. After a few days, you should start to see some germination activity. Count the number of seeds that have germinated and calculate the germination rate.
  8. Continue to monitor the seeds for several days or until you are satisfied with the germination rate.

The soil test for seed viability is a useful way to test the quality of soil and to determine the viability of seeds before planting them. It allows you to identify seeds that are unlikely to germinate and to adjust the soil conditions or seed selection accordingly.

Do Seeds Need Light Or Dark To Germinate?

Some seeds require light, and some require dark. Here are a few common seeds and their requirements.

Need Light To GerminateNeed Dark To Germinate
Brussel SproutsAsparagus
CabbageArtichokes
CauliflowerBasil
CeleryKale
CollardsTomato, Peppers, Eggplant
DillPumpkin
LeeksSquash
OnionWatermelon

Testing the viability of seeds is an important step in the gardening process. By performing the paper towel test or the soil test, gardeners can identify non-viable seeds and adjust their planting strategy accordingly, saving them time and resources in the long run.

Overall, incorporating seed viability testing into your gardening routine is a proactive step towards achieving a healthy and thriving crop. With a bit of patience and care, you can optimize your gardening success and enjoy the fruits of your labor.