Oenothera biennis - Evening Star


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In dark woods, this plant stands out well.

Evening Primrose Family (Onagraceae)

A variable plant with a leafy stalk bloom and lemon-scented large (1 - 2") yellow flowers. Flowers have 4 petals and 4 sepals and stem from a long floral tube. Also has a pronounced cross-shaped stigma. Grows 2 - 5' tall. The leaves are slightly toothed lanceolate 4 - 8" long.

June to October

Fairly common along roadsides, waste places, and in unfurrowed fields with generally dry soils.


This is a night-flowering biennial which opens in the evening (hence the name), but in deeper, darker woods may stay open all the time. There are many different species of this genus.

I didn't quite capture the characteristic 'cross-shaped' stigma in this picture, but at least it's a close-up of the flower.

Medical research on the oils of this plant have revealed some interesting characteristics. The plant may have an anti-clotting factor useful to heart attacks caused by blood clots. Also, it may provide some relief for people suffereing from eczema due to allergy, a skin irritant. There may also be some interest in this plant for people suffering from atopic diseases such as migraine and asthma. The U.S. FDA of course has declared that no drugs containing Primrose oil may be sold in the U.S.



My observations about this plant can be found at:


Another picture and a bit more information is available at the aaa

A picture of the flower plus seeds and other pictures are available at Rutgers