Oenothera

Oenothera is a genus of herbaceous plants in the Onagraceae family, commonly known as evening primroses or suncups. They are native to the Americas, but some species have been introduced to other continents as ornamentals or weeds. Oenothera plants have basal rosettes or spiral leaves that are usually dentate or lobed. The flowers are four-petaled, radially symmetrical, and have a long floral tube. The flowers are usually yellow, but can also be white, pink, purple, or red. The flowers often open in the evening, and last for one day or night. The flowers are pollinated by insects, especially moths and bees, that can reach the nectar in the floral tube. The fruits are capsules that contain many seeds. Oenothera plants can grow in various habitats, but prefer a sunny location and a well-drained soil. They can be grown as annuals, biennials, or perennials, depending on the species and climate.