Roasted beetroot and feta salad should be stored in an airtight container in the refrigerator. It will keep for about 2 days but salad greens will get soggy if stored with the rest of the ingredients. If you're planning to meal prep this recipe, I recommend storing the beets, dressing, and greens all in separate containers, and that way this vibrant salad will last for 3-4 days in the fridge.