Oenothera caespitosa, known commonly as tufted evening primrose, desert evening primrose, rock-rose evening primrose, or fragrant evening primrose, is a perennial plant of the genus Oenothera native to much of western and central North America, in habitats such as talus slopes and sandy plains. It is normally night-blooming. The plant is considered good for rock gardens. There are many subtaxa, referred to as subspecies or varieties.

Description

Oenothera caespitosa grows to 10 centimeters (4 inches) tall. It produces a rosette of lobed or toothed leaves each up to 36 cm long around a woody caudex. It has no stems, with flowers and leaves growing directly from the root crown. The four-petaled white flowers open at dusk and wilt the next morning, turning pink. The petals measure up to 5 cm in width and length. A notch gives them a heart shape.

Ecology

The plant is a larval host to the white-lined sphinx moth. Oenothera caespitosa is dependent on hawkmoths, including the five-spotted hawkmoth (Manduca quinquemaculata) for pollination.

Similar species

Oenothera deltoides is very similar, with short stems and slightly smaller flowers.