Blueberries in a measuring cup
The Best Time To Wash Your Blueberries For Long-Lasting Freshness
For fresher blueberries, wash them just prior to consuming. However, be sure to inspect them right away, removing ones with signs of decay before it spreads to fellow carton mates.
Any unwashed blueberries that aren't ready to be eaten should be refrigerated in the coldest section and stored in breathable packaging, where they will last for a couple of weeks.
When you're ready to enjoy the blueberries, simply wash them under cool running water. For leftover, uneaten berries that have already been washed, they can be refrigerated again.
Gently pat them with paper towels to remove any moisture, and return to a ventilated container, preferably with a paper towel at the bottom and between each layer of berries.