Your seeds last longer if kept at cool temps. Just think about how they overwinter in the ground. A lot of people keep their seeds in the freezer, but from what I understand, they have to be thoroughly dry before putting them in the freezer. Also, when you take them out, let them come to room temp before you open them - it keeps them dry - otherwise, condensation can cause problems, especially if you aren't planting right away.
I've been trying to save those little silica packs that come in shoes and purses....they help absorb moisture and keep it away from your seeds too.
Have a great day
Carol B

Successful seed storage always begins with properly-dried seed. Commercial seed can be assumed to be so in most cases (depending upon where it was found), but home-grown seed should be thoroughly dried prior to storage. Packaging poorly-dried seed in air-tight containers creates high humidity within the container, which can destroy seed in less than a year. See the FAQ's in the link below for more info, or browse through this forum.

If you purchase seed & use it for several years, refrigerated storage will minimize deterioration of the seed. Any refrigerated seed should be stored in air-tight containers such as Ball jars or heat-sealed envelopes, and treated by the same measures mentioned by Ctack above for frozen seed.

If you save your own seed, and grow it fresh each year, you could store seed in zip-locks at room temperature with little loss of germination. In this case, you need only protect from extremes of heat & humidity; a dark place in an air-conditioned home is adequate.

I store much of my bean seed this way, in a metal file cabinet located between a window & an air duct. I block the window in Summer (allowing A/C from the vent) and block the duct in Winter (allowing cool air from the window). The seed is kept cool all year, and has maintained good germination rates for up to 10 years.

If you can't store seeds in cool temps, steady year-round temps are the next best thing. Basements are excellent for this, but the seeds should be in sealed containers to protect from moisture.

Temps above 90 degrees and/or exposure to high humidity will destroy most seed very quickly.

Frozen storage should be reserved for:
(1) Seed that is rare or irreplaceable
(2) Seed with a short storage life (such as onions)
(3) Saved seed which is grown infrequently (such as hand-pollinated seed)
(4) Extending the life of seed collections, thus reducing the need to replenish them annually

A final note regarding air-tight containers, especially zip-lock bags:

Seeds are alive, and while their metabolism is very slow, they require some air to survive. As the storage temperature increases, so does the metabolism, and the amount of air required. If most of the air is squeezed out of a zip-lock when filled with seeds, and the temperature warms, the seeds could literally consume all of the air in the bag - a bag of beans could appear to be vacuum sealed! This could reduce the life of the seed.

In such cases, check the container(s) several times a year, and open them during periods of low humidity to allow fresh air to enter. As a guideline, I would recommend a volume of air within the bag equal to the amount of seed. For large quantities of seed, stir or shake periodically to distribute the air evenly throughout the container.

Here is a link that might be useful: Seed saving FAQ's

Sorry to pull up an old thread, but I had a question about this. (this will be my first year saving seed)

After reading alot of sites about keeping seed cool, but not moist - I thought the best thing to do would be to pack it in a vacume bag so I can store it down in the basement where it's much cooler and I wouldn't have to worry about moisture, not that we have much in colorado.

But after reading what Zeedman wrote about needing some air, I'm guessing that isn't the best idea :(

Would I still be able to store the seeds in the basement, in just the paper envelopes (no plastic envolved). The basement *IS* fully enclosed, however there is a crawlspace to under the house nearby....I would say it's a little more humid then anywhere else in the house, but again, being in dry colorado, that isn't saying much.

Any thoughts or ideas? Thanks in advance!

Laura