Plant Profile

Common Evening Primrose - (Oenothera biennis) is an upright biennial in the Onagraceae family. Its flowering stalk can reach up to 6 feet tall and will form colonies if provided a lack of competition.  It commonly grows in fields, prairies, glades, thickets, waste ground, disturbed sites, and along roadsides and railroad right-of-ways. This plant is highly drought tolerant and naturalizes disturbed areas easily thanks to its status as a pioneer species. As a biennial, the first year will consist only of the basal rosette followed in its second year by the flowering stalk.

The striking yellow flowers open at dusk and close again in the morning when hit by sun, hence the common name of evening primrose.  Fruits are capsules (narrow seed pods to 1 1/2” long) which split open when ripe to release numerous seeds (up to 100 seeds per capsule). The flowering plant will then die after setting seed, but will naturalize in the landscape thanks to its profuse seed dispersion. A unique feature of this plant is that the flowers are fertilized by night-flying moths thanks to the attractive mild lemon flower fragrance and by bees in the early morning before closure. 

It is a very important native plant with a long bloom time benefiting nectaring moths, butterfiles, caterpillars and many kinds of bees. Much of the life cycle of the stunning pink Primrose Moth (Schinia florida) can be in the Common Evening Primrose plant.  The small green larvea of the Primrose Moth will feed on the flowers and seed of the plant. Consider adding a few of these striking plants in areas that you might otherwise struggle to grow other plants.