• Evening primrose is naturalized in the United States.Lidia Rakcheeva/iStockphoto/Getty Images
  
  Evening primrose is an annual plant that is known botanically as Oenothera lamarckiana. Evening primrose is a member of the Onagraceae family, and is naturalized within the United States. The flowering plant commonly appears in meadows, alongside roads and on fence lines. It is notable for its flowers, which are light yellow in color.
  
  

Description

• Evening primrose tends to grow to heights of between 2 and 4 feet. It produces pale yellow flowers that are situated over sturdy and tall spikes. The stem is also spiked. During the late afternoon, the blossoms of the plant open up, all the way into the night. Before morning arrives, the blossoms close up again.
  
  

Cultivation

• Evening primrose is highly adaptable to many different types of soil. The plants grow best in soil that is mildly acidic and well drained. Evening primrose thrives when grown under full sun, and is tolerant of drought. The plant requires regular watering, but it is important to make sure to not water it excessively. Evening primrose can be propagated via seed. The flowers bloom during the months of May, June and July every year. The germination process takes between 15 and 30 days. The plant attracts birds, butterflies and bees.
  
  

Evening Primrose Oil

• Evening primrose oil is extracted from the flowering plant, and offers an array of alternative medicinal uses. Evening primrose oil has been used for the treatment of medical conditions including endometriosis, premenstrual syndrome, high cholesterol, heart disease, psoriasis, eczema, multiple sclerosis, asthma, Alzheimer's disease, cancer, intestinal and stomach diseases, hyperactivity, diabetes, acne and circulation issues. However, its use in treating all of these conditions has not been approved by the FDA.