Buckwheat flour should be stored in a cool, dry environment in a sealed airtight container. Typically, baking enthusiasts store whole grain flours like buckwheat in a cabinet or pantry where it can last around 1-2 months. However, if you want to prolong the life cycle of your flour for three to six months, try storing it in a refrigerator or freezer in a sealed container. This can be ideal if you use flour sporadically but always want to be prepared when your inspiration strikes for your next creation.