Oenothera

Evening Primrose
Onagraceae
Perennials

Valued for showy, four-petaled, silky flowers in bright yellow, pink, or white. Some types display their blossoms during the day, others open in late afternoon and close the following morning. Flowers of some are fragrant. Plants succeed in tough, rough places.

Oenothera caespitosa

Native to western U.S. Clump to 8–12 in. high, 2 ft. wide, with many rosettes of narrow, fuzzy gray-green leaves. Fragrant, 3–4-in. flowers fade from white to pink; they open in the evening. Blooms heavily in late spring,early summer.

Oenothera macrocarpa

Native to south-central U.S. Grows 6 in. tall and 2 ft. wide, with narrow, lance-shaped leaves to 3 in. long. Late spring to early fall, bears pure yellow, 4-in. flowers that remain open all day. Large winged seedpods follow the flowers. Good in rock gardens. Give partial shade in hottest climates.

Oenothera speciosa

Native to southwestern U.S. and Mexico. To 1 ft. high and 3 ft. or more wide, spreading by rhizomes. Forms rosettes of medium green, oblong to lance-shaped, 1–3-in.-long leaves. Fragrant, 2-in. flowers are white to pinkish, aging to pink; despite plant’s common name, they open during the day. Blooms spring or early summer into fall, then stems die back. Good ground cover for dry slopes or parking strips, but can be aggressive and is potentially invasive.

Oenothera stubbei

Native to Mexico. Evening-blooming plant that forms a dark green mat 5 in. high and 4 ft.wide; prostrate stems root along the ground, forming offset plants. Narrow leaves to 2 1/2 in. long. Yellow, 2 1/2 in. flowers rise on individual stems 6–8 in. above foliage. Blooms most heavily in spring, sporadically throughout the rest of the year. Endures heat and drought but does better with occasional water.