It’s getting harder and harder for me to figure out what these flowers are. After spending quite some time on this one the most I’ve been able to conclude is that it might be some variety of Oenothera, commonly known as Evening Primrose.

According to Wikipedia:

Oenothera is a genus of about 145 species of herbaceous flowering plants native to the Americas. It is the type genus of the family Onagraceae. Common names include evening primrose, suncups, and sundrops. They are not closely related to the true primroses (genus Primula).

The species vary in size from small alpine plants 10 centimeters tall, such as O. acaulis from Chile, to vigorous lowland species growing to 3 meters, such as O. stubbei from Mexico. The leaves form a basal rosette at ground level and spiral up to the flowering stems. The blades are dentate or deeply lobed (pinnatifid). The flowers of many species open in the evening, hence the name “evening primrose”. They may open in under a minute. Most species have yellow flowers, but some have white, purple, pink, or red. Most native desert species are white. Oenothera caespitosa, a species of western North America, produces white flowers that turn pink with age. One of the most distinctive features of the flower is the stigma, which has four branches in an X shape.

If Google search results are any indication Evening Primrose Oil is a popular dietary supplement. One vendor describes it as follows:

This 100% pure evening primrose seed is prized for its abundant food, health, and cosmetic benefits. Evening primrose is a common wildflower found in North America, Europe, and parts of Asia. The yellow flowers only open in the evening, hence their common name. Evening primrose has been used throughout in Europe since the seventeenth century.

This particular oil should be kept refrigerated to help prolong shelf life. Because of its many health benefits, evening primrose seed oil is truly a wonderful food additive. It may be taken alone, or can be drizzled on top of salads or other prepared meals. For cosmetic use, evening primrose oil should be added after any preparation steps that require heat. Refrigeration is recommended for this oil.

However, A now archived article of uncertain age on Drugs.com states:

Evening primrose has been used in alternative medicine as a possibly effective aid in treating nerve damage caused by diabetes, and osteoporosis.

Evening primrose has also been used to treat asthma, eczema, attention deficit- hyperactivity disorder (ADHD), hepatitis B, high cholesterol, liver cancer, breast pain, obesity, menopausal hot flashes and night sweats, premenstrual syndrome (PMS), and skin or joint symptoms of psoriasis. However, research has shown that evening primrose may not be effective in treating these conditions.

Evening primrose may have been combined with other plants or extracts in a specific preparation to treat these conditions .

Other uses not proven with research have included chronic fatigue syndrome, dyslexia, coordination and movement problems, diaper rash, dry eyes, rheumatoid arthritis, multiple sclerosis, ulcerative colitis, schizophrenia, Alzheimer’s and other conditions.

It is not certain whether evening primrose is effective in treating any medical condition. Medicinal use of this product has not been approved by the FDA. Evening primrose should not be used in place of medication prescribed for you by your doctor.

Of course the flower in the picture may not be Evening Primrose at all and all of the information above irrelevant.