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Using Old Seeds

Many people are starting seeds for their fall garden, and a common question we hear is, “Can I used ‘expired’ seeds?” The answer is yes! Many seeds are viable years past the expiration date on their package. What changes over time is their germination rate [will decrease year after year]. As I start transplants for my community gardens this season, I am mainly using seeds that expired in 2012. Before seeding a tray, I do a germination test on the seeds I am using to make sure most of the seeds are still viable. (Otherwise I could end up will a lot of empty cells.) To determine the germination rate, I take 10 seeds from a the pack of seeds I am testing, and then lay the seeds out on a damp paper towel. I then fold the paper towel into a square to ensure the seeds don’t fall out, and place it in a clear plastic sandwich bag. I tape the sandwich bag to a window and label exactly what package of seeds I used and the date I started the test. After a couple of days you should see seeds starting to sprout. Depending on the type of seed you use, it could take 10-14 days for seeds to start sprouting. If your seeds have not sprouted after 3 weeks, it is more than likely that they are no longer viable seeds. To determine the actual percentage (or germination rate) of seeds that are still viable, simply divide the amount of seeds that sprouted by the number of seeds total that you tried to sprout. In this case, if only seven of my seeds sprouted then I had a germination rate of 7/10= 70% [which is not bad for ‘expired’ seeds.] For more information on using seeds in your garden visit,
E. Santiago Gomez