[Quix]

heirloom seeds . . . such as from

tomatofest.com

insure dry . . . cool . . . if dry . . . and dry weather, low humidity, store in glass Mason/Ball type canning jars, imho.

Check StanDeyo.com for lots of survival info.

[Bitsy]

You can buy any seeds you want because if things get that bad, you’re going to be up day and night with gun in hand to guard your bounty.

[magslinger]

Heirloom seeds are definitely the way to go. When I was a boy our neighbor gave me some cucumber seeds from his heirloom variety. I planted them every year for a number of years. The vines would produce an abundance of huge (3-4 inch diameter, up to two feet length) cukes. Finding good homes for all of the cucumbers was a bit of a challenge.

After a few years of doing that, I stopped planting them for about five years. I kept the seeds in a wooden box in my parents basement over this period. When I tried again, I got 80+% germination, about the same as when I had been planting every year. Germination rates and how long they will keep will vary with type of seed and the variety, but they have germinated seeds stored cool, dark, and dry for centuries.