When it comes to frozen blueberries, they can last a long time as long as you store them properly. If stored in airtight containers or heavy-duty freezer bags, the quality of frozen blueberries will remain good for up to 12 months. It is important to remember not to overload your containers when freezing – adding too much space can decrease the berries’ lifespan drastically and make them more prone to freezer burn. When thawing frozen blueberries, ensure you don’t leave them at room temperature for too long; any bacteria present may increase in number and cause food poisoning if eaten raw. The best way is to cook or bake with them immediately after taking them out of the freezer.