Lythrum salicaria L.

Hairy, perennial herb; stems erect, ± quadrangular, 1–2 m tall, pink towards base. Lvs sessile, 20–95 × 5–27 mm (smaller just below infl.), lanceolate, oblong-lanceolate or narrow-elliptic, with short hairs beneath, especially on veins, sometimes becoming glabrous above, entire, ciliolate; base usually rounded to cordate, sometimes amplexicaul; apex usually acute, sometimes subacuminate. Infl. terminal, branched, main axis to nearly 25 cm long, densely hairy. Fls usually dense except on lower branches, usually in whorls of 3–7, sometimes 1–2 in axils of bracts, or to 15 per whorl, tristylous. Pedicels c. 0.5 mm long; bracteoles much > pedicels. Calyx 6–8 mm long, broad-cylindric, often purplish, with prominent ribs, hairy; calyx lobes ± triangular; epicalyx segments 1.5–2.5 mm long, subulate, much > lobes, densely hairy. Petals 6, 9–15 mm long, rose or rosy purple, crumpled; claw short; limb oblong-elliptic or oblong-obovate. Stamens usually 12, usually 6 exserted and 6 included, rarely all exserted. Style to 7 mm long, with stigma at varying levels in different plants. Capsule included, 3–5 mm long, ellipsoid or ovoid-ellipsoid, blackish. Seeds 0.8–1.2 mm long, narrow-ovoid to almost oblong, ± flattened and keeled on one side.

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

Flowering: Dec.–Feb.