What's eating my plectranthus scutellarioides 'black dragon'?

Plectranthus scutellarioides 'Black Dragon' (coleus) is primarily grown as a houseplant or summer annual and is most threatened by mealybugs, spider mites, and aphids. Whitefly and fungus gnats can also cause problems. The velvety dark foliage does not deter these common indoor or warm-season pests.

White waxy fluff in leaf axils and stem joints; plant wilts and foliage yellows as insects suck sap; sticky honeydew attracts sooty mould. Dab individual bugs with a cotton swab dipped in 70% rubbing alcohol; spray with insecticidal soap or neem oil; isolate infected plants immediately.

Fine stippling on dark leaves losing their colour intensity; very fine webbing on undersides in dry, warm conditions. Raise humidity around the plant; spray undersides of leaves with water then apply neem oil or insecticidal soap; repeat weekly.

Soft colonies on tender new shoot tips and beneath young leaves; curling growth and sticky deposits on the foliage. Pinch off heavily infested tips; spray with insecticidal soap; if grown outdoors, encourage lacewings and ladybirds as natural predators.

Adult gnats are a nuisance; larvae in the compost feed on fine roots and damage cuttings, causing stunted growth and wilting. Allow compost to dry between waterings; apply a layer of horticultural sand on the soil surface; drench with Steinernema feltiae nematodes.