The spicy flavor of a fresh radish is most pronounced immediately after harvest. Proper storage helps retain the flavor and quality of any radishes you can't use right away. Harvest radishes when the roots are about 1 1/2 inches in diameter. Smaller roots haven't developed their full flavor and larger roots become tough and woody. Prepare and store the radishes immediately after pulling so the roots don't begin to decline or lose their signature flavor.
Cut the tops off the radish with a sharp, clean knife. Leave 1/2 inch of the stem attached to the top of the bulb.
Place the radishes in a perforated plastic storage bag. A perforated bag allows air circulation while retaining moisture during storage. Store in an open plastic bag if you don't have perforated bags.
Store the bagged radishes in the vegetable crisper drawer of the refrigerator. Store the radishes for up to a month in the refrigerator.
Inspect the radishes once weekly. Use them immediately if they begin to discolor or develop soft spots.