Well, history records that Egypt was able to keep wheat stored well enough to survive a drought and famine that lasted for seven years. Remember that the kernel of wheat is a seed, and seeds are designed to remain inert as long as they are kept relatively cool and dry. So, protection from pests and elevated moisture levels would be the primary keys to longevity in storing wheat.
right right... now if I could win the lotto I might be able to get me a rural holdout before everything falls apart... in the fall? winter?