But what about those left-over seeds from last season that you left in a hot garage all summer? Or those heirloom seeds that your aunt gave you three years ago? Did you accidentally nuke your seeds by forgetting to store them in a cool, dry place? Are those older seeds still reliable?
To find out, you need to do a quick and easy experiment called a germination test. All you need are paper towels, a spray bottle full of water, small zip lock bags, and a permanent marker. Here’s how:
- Rip a paper towel sheet into quarters. Spread a piece of paper towel on a cookie sheet or other water-proof surface.
- Using a spray bottle, mist the paper towel with water (if water beads up around your fingertip when you press on the paper towel, it’s too wet).
- Take 10 seeds of a given variety and evenly space them in the middle of the paper towel.
- Roll up the paper towel so the seeds are encased in a long, narrow strip of paper towel.
- Using a permanent market, label a zip lock bag with the name of the variety you are testing.
- Place the rolled-up paper towel with the seeds into the labeled zip lock bag and seal it.
- Repeat the process for any additional varieties you want to test.
- Place the bags in a warm spot (between 70 and 80 degrees) such as on top of the refrigerator or on a high shelf near a heating vent.
- Check the seeds in a week and count how many seeds sprouted.
- If seven or more seeds sprouted, the seeds are viable and can be planted normally in your garden next spring. If less than three seeds sprouted, you should probably discard that variety. For varieties with germination rates between 30 and 70 percent, be sure to over-plant to make up for the loss in seed viability.
Note: Most seed varieties will last for several years. However, carrot, parsnip, parsley, chives, onion, and leek seeds are generally only good for one year and should be reordered each year.