Oenothera lamarckiana

Oenothera lamarckiana (evening primrose or evening-primrose) is a plant species in family Onagraceae, indigenous to North American Plains (all regions of North America). The species was important to the study of genetics, the debate about the cause of evolution, whether that was natural selection or one of the alternatives such as mutationism, and particularly to the discovery of polyploidy. Oenothera lamarckiana is an annual plant, living just one year. It grows quickly up to 24-60 inches. This primrose species blooms heavily, and dies with first frost. Flowers are open in the afternoon and are closed by morning. Flowers are yellow, in a spike of spurred blooms. Weight of seeds is 952,543 per pound. Oenothera lamarckiana is a very adaptable plant, but it needs full sun, average moisture, and well-drained soils. It is easily grown from seed.