Oenothera biennis L.

Biennial, taprooted herb. Stems to c. 1 m tall, sometimes branched, with scattered long white hairs, with or without hairs with bulbous red bases. Rosette lvs long-petiolate; lamina to 27 × 4 cm, lanceolate to elliptic, with short curly hairs, sometimes hairs ± appressed; midrib pale; margins subentire to denticulate or sinuate; base cuneate to attenuate; apex acute. Cauline lvs with winged petiole or apetiolate; lamina smaller but otherwise similar. Infl. many- or few-flowered, its stem simple or branched; rachis and ovary densely clothed in glandular hairs. Fls crepuscular. Floral tube 3–4.5 cm long, slender, densely clothed in glandular hairs. Buds narrow-lanceolate, erect. Sepals to 3.5 cm long, glandular-hairy; apices mucronate, not or only slightly divergent. Petals 2–3.5 cm long, broad-obovate, yellow. Style exserted by 0.7–2.5 cm, < to > stamens. Capsules 1.5–3.3 cm long, cylindric but widening slightly towards base, ribbed, densely clothed in glandular hairs. Seeds 1.5–2 mm long, sharply angular, very irregular.

[From: Webb et al. (1988) Flora of New Zealand. Volume 4.]

Flowering: Nov.–Mar.