Seed Sense: Can I use leftover seeds?

We get some pretty seedy questions on our Facebook page. We'll share our answers to the most popular ones here on our blog. If you have more suggestions to add to our answer, please feel free to leave a comment below.

Q: " How long can most seeds stay in storage and still remain viable? I was given some bean, zinnia, squash and dill seeds that are 3-4 years old and had been stored in plastic containers." - Jan Lygs

A: Most seeds will last at least a few years. While alliums (onions, leeks, chives, garlic chives) and umbels (carrots, dill, parsnips, parsley) last only a couple of years, cucumbers and melons can last up to ten!

Typically, your germination rate will go down a bit every year. For each year you keep them we suggest starting 25% more seeds, just to be sure you'll have enough  germinate. You can also find out the germination rate with a simple test–here's how.

We also recommend storing your seeds somewhere cool, dark, and dry. We don't advise freezing seeds, as this can cause damage if the seeds aren't dry enough. If you keep them in the fridge make sure they are in a tightly sealed container. It doesn't hurt to throw in a silica gel packet (often found in shoe boxes and other consumer packaging). Saving your own seeds? The same storage rules apply. Just make sure the seeds are completely dry before storing.