Evening primrose

Evening primrose (Oenothera biennis) is a species of Oenothera, a wild flower native to eastern and central North America. It is also called common evening primrose or evening star because its showy, bright yellow blossoms open at night and close during the daytime. The plants have a two-year life cycle (that is, they are biennial) and can range in height from 10 inches several feet. Pollinated by bees, they are also frequently deliberately cultivated by gardeners.