Plectranthus comosus or the woolly plectranthus is a soft exotic shrub found in South African gardens and local lists of troublesome invasive plants. It grows long stem-tip spikes of blue flowers. The soft woolly stems are brittle. The leaves are large, ovate to elliptic, soft and hairy.
Possibly native to India, the plant invades in South Africa, usually near places where it has been planted. The SAPIA Newsletter Number 11 of April 2009 published by the ARC-Plant Protection Research Institute mentioned this plant as an invader in the former Transkei region.
P. barbatus of Central Africa is very similar, if not the same, as some sources present them (Blundell, 1992; www.zimbabweflora.co.zw).