Photo Credit: Annette Casados, USFWS

This beautiful flower often blossoms in the evening, hence the name, Evening-primrose.

• Belongs to the Evening primrose family, Onagraceae.
• Annual that grows 18 inches in height, usually in patches of erect, pale, velvety stems.
• Inflorescence (flowering part of the plant) consists of four white, heart shaped petals, four sepals, four to eight stamens (male reproductive organ on a flower), and a four chambered ovary.
• Leaves are alternate, oblanceolate (inversely lanceolate, with attachment at the narrower end) to deeply pinnate (compound leaf with leaflets arranged on opposite sides of the axis), often wooly and have a grayish-green color.
• Fruit is a nut like structure or capsule with seeds.
• Grows in disturbed soils on sandy slopes and along roads.
• Oenothera means “wine tasting” in Greek, referring to the old use for the root.

The oil from the plant is one of the world’s richest sources of natural unsaturated fatty acids. Unsaturated fatty acid is often helpful in cases of obesity, mental illness, heart disease and arthritis. In 1999 the US listed O. albicaulis in the Top Ten Dietary Supplements in Popular Herbs in the US Market, 1997 source by M Blunenthal.

For a complete Refuge species list

For in-depth plant information
connect with the U.S. Dept Agriculture Plant Data Base

Last Updated: 1/14/09

Blooming Times On The Refuge

April-June: Sand lily

May-June: Ball cactus, Prickly pear

May-July: Scarlet butterfly weed, Prairie evening primrose, Blanket flower, Low daisy

May-August: Blue flax, Wine cup

June-August: Rocky Mountain beeplant, Wavy leaved thistle, Blazing star

June-September: Prairie coneflower, Hairy golden aster, Evening star, Sunflower, Scarlet globemallow

July-September: Black eyed susan, Purple prairie aster

NORTHERN PRAIRIE WILDLIFE RESEARCH CENTER