Plectranthus bojeri (Benth.) Hedge

Erect or ascending annual or short-lived perennial herb, up to 1 m tall, sometimes taller. Stems 4-angled, sometimes rooting at the lower nodes, variously hairy and often with red sessile glands. Leaves opposite, ovate-rhombic, up to 12 cm long, sometimes purple-tinged, pubescent and with scattered red sessile glands, margin more or less deeply crenate-serrate; petiole up to 6.5 mm long. Inflorescence usually lax with many, more or less widely separated, 10-30-flowered verticils. Corolla blue to deep purple, often with reddish sessile glands,2-lipped; upper lip erect, shorter than lower lip; lower lip boar-shaped, often hiding the stamens. Nutlets ovoid, c. 1 mm long, brown, speckled reddish.

Widespread in tropical and southern Africa and Madagascar