Broccoli can stay fresh for 3 to 5 days in the refrigerator. After that time, it may develop strong, unpleasant flavors. Do not wash the broccoli before storing, as it can become moldy; instead, store the broccoli in a perforated plastic bag in the vegetable crisper.
Wash broccoli just before using, but do not soak cut broccoli in water, as it has water-soluble nutrients that may leech out. To store fresh broccoli for longer periods of time, blanch it in boiling water for 4 minutes, submerge it in an ice bath and store it in a freezer-safe container in the freezer.