My family doesn't buy flour (I had to learn how to do that when I got to college), instead we buy wheat from the LDS Bishop's Storehouse -- because they have the best prices -- and grind it into flour in our kitchen wheat grinder.
But, because we buy our wheat in bulk we store it in the basement until we can use it which means we have to keep it from mice or moisture or bugs and we do that by freezing it for three days in a chest freezer and then keeping it in 5-gallon buckets.
We get our 5-gallon buckets from a bunch of different places: our honey and our oil come in them, we got a bunch with our maple tapping supplies, and once we had a deal with a cake store in town where they gave us their empty frosting buckets in return for a loaf of fresh whole wheat bread.
We keep all our empty 5-gallon buckets stacked high in the root cellar with grocery bags in between them to keep them from sticking. unfortunately they still stick a little bit and my brothers have to play tug of war.
We but the paper bags of wheat directly into the buckets and then on goes the lid, a strip of packing tape on which we write the date and what's inside. Sometimes we write some little fun fact on it as well such as: William was baptized this year, or ... today it is raining. Those little messages from the past are fun to read a couple years later when we actually use the wheat.
After the buckets are labeled we just stack them in the root cellar for years later. It's a good feeling to be ahead like this! We just need to get ahead in all areas.
Next stop: Pineapple and Bean & Bacon Soup