Classification
 Nomenclature
Scientific Name:
Ballota nigra L.
Vernacular Name(s):
Black horehound
 Description

Perennial herb, with hairy stems to c. 1 m tall. Petioles 1–3 cm long. Lamina of upper cauline lvs 2.5–5 × 2–3 cm, ovate or ovate-oblong, densely hairy on both sides, strongly crenate; base subcordate; apex acute. Verticels dense; bracts cuneate, serrate or crenate-serrate. Bracteoles < calyx, ± filiform. Calyx 6–9 mm long, with nerves densely hairy; teeth ovate, acuminate. Corolla 12–15 mm long, pinkish to purple or white, almost glabrous outside; middle lobe ovate and slightly reflexed. Filaments hairy at base. Nutlets not seen.

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

 Biostatus
Exotic
 Phenology

Flowering: Feb.