Plectranthus hail from warm temperate to tropical areas of the world and grow in shadier parts of the garden under trees in very ordinary soil where many plants do not thrive. They grow quickly and are tolerant of drought and root-competition.
Plectranthus ciliatus from South African forest regions, is a groundcover plant, growing to 30-40cm tall, often incorrectly sold under the name of P. oertendahlii. It has an autumn veil of long spires of dainty lilac-tinged flowers across its purple-veined and purple-backed leaves. It will grow in the most uncongenial shady places and can form a dense carpet under trees or shrubs, and is stunning when in full bloom. It associates well with dark purple-leafed foliage plants such as bromeliads, Tradescantia pallida 'Purple Heart' or black taro (Colocasia esculenta 'Black Magic') to echo its darker tints. It makes an excellent carpet beneath autumn-flowering Camellia sasanqua, shrub and cane Begonia and Justicia carnea.
Like most groundcover Plectranthus, it looks effective grown in a hanging basket. The cultivar 'Nico' looks like a larger-leaved version, with very striking purple veins in its textured foliage, but it appears to be derived from Plectranthus ambiguus. The stems should be cut back fairly hard after flowering (or in early spring in cooler areas if there is the risk of frosts). The plant dislikes hard frosts, but if grown under a canopy of trees, will usually be well protected from milder frosts. It enjoys being mulched and fed occasionally but is really a plant that will grow despite being neglected! It is very easily propagated from cuttings in spring and autumn. All Plectranthus need to be replaced by new cuttings every so often as they get a bit straggly after a few years.