Oenothera L.
Annual, biennial or perennial herbs, caulescent or acaulescent, sometimes almost shrubby. Lvs alternate or in basal rosettes, simple and entire to pinnatisect or 2-pinnate. Fls in terminal leafy spikes, 1 or few in axils of subtending lvs. Axis of fl. produced well beyond ovary to form a prominent deciduous floral tube. Sepals 4, reflexed at anthesis, sometimes white to red. Petals 4, generally large (> 10 mm long), usually yellow, white or pink. Stamens 8, equal or the 4 outer or antisepalous ones longer; anthers usually versatile and not erect. Ovary 4-celled; stigma capitate to 4-lobed. Capsule loculicidal, 4-valved, ± elongated, membranous to woody, free or fused with subtending bract, sometimes winged. Seeds numerous, often angular, occasionally winged.
Key
c. 120 spp., America, mostly warm temperate regions. Naturalised spp. 7.
In addition to the spp. described below, a few others are cultivated in N.Z.
