Evening Primrose

The evening primrose displays four slightly notched petals and pale yellow stamen in the early evening and morning.

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Evening primrose is named for flowers that are open in the evening and partially or fully closed during the day. Most of the evening primroses in the southwest are white or yellow in color and feature large, dramatic petals, unlike most other desert flowers. These papery delicate petals give the flowers a look of grace and beauty that is rarely seen in the arid environments they grow in. Evening primroses produce new blossoms every 1 to 2 days, keeping a tidy look to each rosette of hairy basal leaves.

Usually only growing to about 6 or 8 inches, evening primroses may easily be missed by humans during the daytime hours. However, those who know what to look for may visit the plant for nourishment. Hummingbirds may drop in on the plant in the early morning and evening to collect nectar and insects, such as the Japanese beetle, visit during the day to feast on the tender leaves.

Pollination of the flowers is thought to be provided by hawk moths. As the flowers open in the early evening they begin to release fragrance and nectar. They show their white or pale flowers to further attract the moths. The flowers also provide a platform for the heavy bodied moths to land on. Flying from one flower to the next, pollen is distributed on the legs and body of the moth ensuring another generation of evening primrose.