About Oenothera lindheimeri (Engelm. & A.Gray) W.L.Wagner & Hoch
Oenothera lindheimeri is a perennial herbaceous plant that reaches 50 to 150 centimeters (20–60 inches) in height. It grows densely clustered branched stems from an underground rhizome. Its leaves are finely hairy, lanceolate in shape, 1 to 9 cm (1⁄2–3+1⁄2 in) long and 1 to 13 mm (1⁄16–1⁄2 in) wide, with coarsely toothed margins. Flowers are borne on an inflorescence 10 to 80 centimeters (5–30 in) long; the blooms are pink or white, 2 to 3 cm (3⁄4–1+1⁄4 in) in diameter, with four petals 10 to 15 mm (3⁄8–5⁄8 in) long and long, hairlike stamens. Flowering occurs from early spring through to the first frost. Oenothera lindheimeri is commonly grown as an ornamental plant. It is used in garden beds or containers to add accent color and delicate texture. It grows best in full sun and can tolerate long periods of drought. Multiple cultivars have been selected for different flower colors: 'Whirling Butterflies' has nearly pure white blooms, while 'Cherry Brandy' and 'Siskiyou Pink' have darker pink flowers. For some cultivars, petals are white at dawn, then turn pink before falling off at dusk. While it is a perennial rated hardy for USDA Zones 5(6)-9, it does not always overwinter reliably, and is often grown as an annual outside its native range. In colder climates, a thick winter mulch is required for survival. This species has been awarded the Royal Horticultural Society's Award of Garden Merit.
