Evening Primrose Oil

Evening primrose oil is pressed from the seeds of the evening primrose plant (Oenothera biennis), a wildflower native to North America whose seeds are harvested after the plant's yellow flowers, which open in the evening, have gone to seed. Like borage oil, it is valued chiefly for its gamma linolenic acid content, an omega six fatty acid uncommon in most other plant oils, and is sold mainly as a nutritional supplement rather than used as an everyday cooking oil. Commercial cultivation for seed oil is concentrated in North America, Europe and China.