The common evening primrose is native to Virginia and was sent to England in the early 1600s, feeling quite at home there and has naturalized in several parts of Britain. 

The Missouri primrose was identified first in 1811. 

The evening primrose has both roots and leaves that are edible. The roots are sometimes eaten in France and some herbalists believed that the plant can be used medicinally for asthma and whooping cough. 

The botanical name for evening primrose, Oenothera, is from the Greek, which is interesting since all members of this plant family are natives of the New World. 

Oenothera fruticosa is hardy zones 3-8 and blooms in late spring, and its common name is sundrops. The nectar attracts butterflies and hummingbirds, and it grows 12-24 inches high. 

The pink evening primrose is Oenothera speciosa, and the flowers open in the evening and close in the morning. The white form is called 'Alba'. 

The Missouri evening primrose 'Missouriensis' has lemon yellow flowers on low red stems. It blooms from May through August and enjoys a dry soil. 

Divide these plants in spring or fall. Sometimes these primroses are aggressive growers, especially the pink ones, but they also often die out after a while. They are popular pass-a-long plants and easy to grow and are fun.