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.
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 shoeboxes and other consumer packaging).
Saving your own seeds? The same storage rules apply. Just make sure the seeds are competely dry before storing.
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