Testing Old Seeds

I like to test my old vegetable and flower seeds about this time of year because I will be starting some of them inside very soon. I count out 10 seeds from each packet and place them in a row on a half sheet of wet paper towel. Then I roll up the towel and place it in an 8 by 13 inch pan. I can place 10 or more rolled up towels in a pan. I stick a piece of masking tape on the long side of the pan to write the variety of seed in each roll. I use a permanent marker so it doesn’t fade if it gets wet. Sometimes I just number the packets and put the same number on the tape. I check daily and spray the towels with water to keep them moist. I place the pan on top of the refrigerator near the back where it gets heat from the condenser coils.

Some seeds will germinate in less than a week while others may require two weeks or longer. I count the number of seeds which sprout and multiply by 10. This gives me an approximate germination percentage. I write this number on the packet. I usually throw most of the sprouted seeds away after testing. However, if they are expensive seeds or if it is near the time to start them inside I can plant them in pots or trays.

By placing the germination percentage on the packet I know how thick I need to plant the seeds. I use seeds which are as low as 40 or 50 percent. I just double the planting rate on lower germination seed.

By checking the packets and counting seeds for the test I know if I have enough seed for planting. Then I have plenty of time to buy seed for the coming spring. It saves me from running out of seed half way down the row at planting time.