So, the lure of the gardening department overwhelmed you last trip and you now have more seeds than you can plant. How long can you store them for future growing dreams? (This is also the same for seeds you have grown yourself and wish to use at a later time.) As long as they are in the ideal conditions and right kind of containers, most will last 3 years and some will even last a few centuries.
Conditions for Optimal Seeds Storage Include:
Once these conditions have been met you have a wide verity of storage options in terms of what kind of container will work. You can use things such as Ziplock bags, Mason jars, specialty seed organizers, the biggest part is to make sure they are sealable.
Some other key things to keep in mind when storing you seeds is to make sure you are not some seeds are not stored for more than one growing season. This would include all alliums, parsnips, many types of herbs, and celery/fennel (sometimes but not always).
Though most seeds remain viable for years and often decades, the seeds of alliums (anything in the onion family, including shallots, leeks, chives, and scallion) and parsnip often lose their germination by 50% each year, regardless of conditions. Many herbs are also challenging to store. Their thin, fragile seed coat quickly oxidizes, causing them to lose germination fast. Store them as best you can and sow them more densely than you otherwise might in the seasons to come.
WAIT! Before you compost your five-year-old onion seed, EAT THEM! Next time you look at an ‘everything’ bagel, you’ll recognize familiar little black allium seeds in the mix. I love their onion essence toasted in lots of dishes, especially curries and stir-fries. Note: if they are not black, they have a coating on them and are best sent to the compost, after all.
Freezing seeds can be an option for some that want to go with the if cool is good cold is better method of operation. This has been seen to not make much of a difference in terms of how long they can be stored for in comparison to cool storage, but you will need to just make sure they are a dry as possible before freezing them.