Checking for Seed Viability
Do you have packets of seed that did not get used up last year, or even from a few years ago? Are you wondering if they are still good to use or if you need to go out and purchase new seeds? Here is an easy way to check to see if the seed package you opened three years ago is still viable.
Moisten a paper towel and place 10 to 20 seeds of one variety on it. Roll up the towel and place it in a plastic bag labeled with the seed variety. You can keep it on the kitchen counter at room temperature while you are testing. Check the seeds after 2 or 3 days, then every day for a week or two if needed; different varieties have different timing for germination. Count the number of germinated seeds and divide them by the number of seeds tested. This will give you the germination percentage. Less than 80% germination means your seeds still have some viability but that you will need to sow them more thickly in order to get a good crop. Seeds with less than 50% germination may not be worth the trouble and you can go seed shopping!
Washington State University research shows that seed viability is variable. Seed that can remain viable for 5 – 6 years includes cucumbers, lettuce, melon, and spinach. For 3 – 4 years; asparagus, beans and peas, beets, cabbage family, carrots, eggplant, squash and pumpkins, and tomatoes remain viable. Low on the viability scale, corn, onions and leeks, parsley, parsnips, and peppers can remain viable for only 1 – 2 years.
Store unused seeds in a cool, dry place to ensure their maximum germination rates.