This wild onion grows from Canada to the Carolinas and resembles a scallion with broad leaves. Also known as wild leek, ramp has an assertive, garlicky-onion flavor. It can be found — usually only in specialty produce markets — from March to June. Choose those that are firm with bright-colored greenery. Wrap tightly in a plastic bag and refrigerate for up to a week. Trim the root ends just before using. Though the flavor of a ramp is slightly stronger than the leek, scallion or onion, it can be used — raw or cooked — in many dishes as a substitute for any of those three.