Oenothera biennis is a species of gemus oenothera belonging to family of Onagraceae.It grows in habitat of terrestrial wetlands, therefore is native to eastern and central America. The plants are very tall ranging from 4 to 5 feet in height. The stem is straight, solid, soft-hairy, rosy and branching forming a shrub. It has the life span of two years. The leaves are simply lobed but not removed from leaflets leaflet. The Flower petal is of colour yellow and the flower is radically symmetrical.