Allium unifolium, American or One Leaf Onion, is native to the west coast of the USA where it is found in California and Oregon growing in moist soils amongst pine and mixed evergreen forest in the coastal mountains. It has umbels of attractive open relatively large star-shaped flowers that are rose pink in colour and are held upright to a height of about 35-40cm. It flowers from May through to June, the flowers turning papery and lasting longer in this dry state. It produces no bulbils but slowly spreads by new bulbs being produced on the ends of long thick secondary rhizomes. These replace the old bulb with each producing 1-3 new bulbs a year.