Oenothera elata (Hooker's Evening Primrose) is a tall biennial with one or more upright, unbranched stems boasting a profusion of large bright yellow flowers, 3 in. across (7 cm), with four heart-shaped petals in early summer to early fall. Borne singly along stout, reddish stems, the sweetly scented flowers open sequentially from the bottom upward and turn orange with age. As the common name implies, they open in the evening and remain open through late morning. The flowers are pollinated by moths, bees and butterflies. Emerging from a basal rosette of long, oblong leaves, 12 in. long (30 cm), the stems are covered with short, soft hairs and clasped by smaller stem leaves. The flowers are followed by cylindrical capsules that turn woody when mature, splitting lengthwise to release tiny seeds that ripen from late summer into fall. Songbirds feast on the seed. This Evening Primrose completes its life cycle in 2 years, its basal leaves becoming established the first year, while flowering occurs the second year. Providing a bold splash of color in the summer garden, this prolific seeder is perfect for moist or seasonally wet gardens.

• Grows 3-5 ft. tall (90-150 cm) and 2-3 ft. wide (60-90 cm).
• Best in full sun to part shade in virtually any moist, well-drained soils. Some drought tolerance once established.
• Great choice for cottage gardens, wildflower gardens or naturalized areas.
• No serious insect or disease issues.
• Propagate by seed.
• Native to much of western and central North America.