To gain the most health benefits of microgreens, eat them as fresh as possible. Microgreens, like most vegetables, are vulnerable to rapid changes in humidity. Make sure you store them in an environment that keeps their moisture level at a healthy medium. The best way to store microgreens is to place them between damp paper towels, put them in a resealable plastic bag or container and pop them in the fridge. Microgreens will last for about a week.