(Oenothera biennis)
Oenothera biennis is a species of Oenothera, an herbaceous flowering plant
native to America which can be found from Newfoundland to Alberta. Common names
for the Oenothera biennis include; evening primrose, evening star, suncups and
sundrops.
Oenothera biennis is a biennial (as the name suggests) or
short-lived perennial herb producing strong fleshy roots and a basal rosette of
lance-shaped leaves in the first year. In the second year, the stems grow and
develop beautiful yellow, tubular flowers.
The "evening" in the name relates to the fact that it is
a night blooming plant that will produce a succession of short lived blooms
from late spring until mid-summer if the dead flowers are removed promptly. The
flowers are hermaphrodite, produced on a tall spike and only last until the
following day. The flowers open-up visibly fast, every evening producing a lovely
spectacle. Their flowers open in the evenings for night flying moths to
pollinate them. The Evening Primrose isn't a "primrose," a name best applied
to the genus Primula.
The Evening Primrose has eye-catching bright, lemon-yellow, cup-shaped, flowers that measure
2 to 3 inches across and have a mild lemon-scented fragrance. The glossy rich
green lance-shaped leaves surround spreading red stems. The seed pods are
4-winged and 2 to 3 inch long and are often used in flower arrangements. It has
a spreading growth of 6 to 12 inches in height and 2 to 3 feet wide. The
evening primrose is a great plant for borders and rock gardens. It is hardy in
zones 5 to 8.
The Evening Primrose prefers to be grown in full sun but will
tolerate some light shade in the afternoon.
It is an easy plant to take care of; it spreads enthusiastically
and might need control. The evening primrose attracts butterflies and birds.
Evening primrose extracts were used medicinally by both Indians
and early settlers. The oil from the seed of the evening primrose plant is a
gamma-linolenic acid, which is an omega-6 essential fatty acid. The oil is used
to treat skin disorders such as eczema, psoriasis, and acne. Evening Primrose
oil is also used for treatment of many ailments among them; rheumatoid
arthritis, osteoporosis, premenstrual syndrome, chronic fatigue syndrome. In
foods, evening primrose oil is used as a dietary source of essential fatty
acids.