Allium cratericola is a species of wild onion known by the common name Cascade onion. It is endemic to California, where is an uncommon member of the flora in several of the state's mountain ranges. This onion grows a short stem up to 10 centimeters tall from a brown-coated oval-shaped bulb. There are one or two long, pointed leaves up to four times the length of the stem. The inflorescence contains up to 20 rosy pink flowers clustered densely together.