coleus, any of several ornamental plants in the mint family (Lamiaceae), grown for the bright colours and patterns of their leaves. The plants were formerly grouped in the genus Coleus, but their taxonomy is contentious and molecular data suggest that the species are distributed across several genera.
Varieties of common coleus, or painted nettle (Plectranthus scutellarioides, formerly Coleus blumei), from Java, are well-known house and garden plants up to one metre (three feet) tall. They have square stems and small, blue, two-lipped flowers borne in spikes. The leaves are often variegated with colourful patterns of magenta and green, though other colour combinations have been developed.
Bush coleus, or blue Plectranthus (P. thyrsoideus, formerly C. thyrsoideus), from Central Africa, reaches a height of one metre and produces sprays of bright blue flowers. The leaves have distinctive venation and are often green with white borders.