How Long Do Seeds Last? Best Practices & A Story

The red-winged blackbirds have returned and we just got eighteen inches of snow!  

Before I sat down with a cup of chaga tea to write you this morning, here is what we did at dawn:

How Long Do Seeds Last?

Friends, I’ve been asked a lot recently:

“Is it worth planting these seeds I didn’t sow last season?”

The answer is yes. Mostly.

Here’s the thing: most seeds will last three to five years kept dry and stable, relatively low temperatures. A kitchen cupboard or desk drawer are perfect places for seeds. So planting seed from the year or two prior is perfect. 

The only exception: anything in the allium family (onion, leek, scallion, chive, shallot) and parsnip. Their seed coat is thin and fragile, so they readily oxidize and lose their germination. These are the only seeds to purchase each year. If you do have extra from years past, sow them more densely than you would if their germination was optimal. 

Many seeds are delicious as seedlings and can be grown as salad mix (kale, chard, lettuce), a perfect way to hedge your bet if germination rate may be low.  

You can always test for germination, but it’s often easiest to simply over-sow and commit to thinning if germination is higher than expected.

Interestingly, there is no golden rule about seed size and longevity. Some large seeds last a decade or more in average conditions (corn and beans, especially) while other large seeds (like okra) lose their germination more quickly.

There is also the ‘100 Rule’ to help maximize your seed longevity. The concept is this: keep the total of humidity + temperature below 100. Having the lowest humidity possible is your goal. Having exact numbers and fancy equipment really isn’t necessary, but the general concept can be very helpful. Also, stable temperatures retain seed germination longer than fluctuating temperatures. 

If you want to store your seeds long-term, know freezing is an option. If seeds are dry enough, they’ll be perfectly fine. To make sure your seeds are sufficiently dry, tuck them in a jar or ziploc bag tightly closed with a dessicant packet (you’ll find them in shoes, vitamins and nori packages) for three days before sending them to the freezer. 

And Now For A Story

A number of years ago I visited the National Conservatory in Washington, DC and low and behold, there was a moss campion flower. It’s sweet lavender blooms barely emerge from its low, mossy tuft of foliage. I’ve seen it countless times on mountain tops (my photo above is from the Chic Chocs in Quebec) and absolutely everywhere in Alaska.This particular plant grew from a seed found 100 feet down, while coring the Siberian permafrost. Miraculously, it grew. Miraculously, it was Carbon Dated. Miraculously, it was ~27,000 years old. 

In conclusion, seeds are uniquely adapted to stay alive on Earth. Give them a little bit of a chance and they will last your lifetime. 

Sow Seeds & Sing Songs,