What's eating my begonia conchifolia?

Begonia conchifolia, a compact rhizomatous indoor begonia, is most susceptible to mealybugs at its rhizome nodes and to spider mites in dry indoor conditions. Its small, rounded leaves make scouting easier than with larger-leafed species. Catch pests early — inspect the underside of leaves and rhizome surface whenever you check soil moisture.

White cottony tufts at petiole bases and along the rhizome; sticky honeydew and yellowing leaves. Remove with an alcohol swab; apply neem oil or insecticidal soap spray covering all surfaces, repeated every 7 days.

Tiny pale dots on leaf surface; fine webbing in joints; leaf edges may brown in dry air. Raise humidity around the plant; mist or wipe leaves; spray neem oil every 4–5 days for at least 3 applications.

Larval root feeding in persistently wet compost; flying adults emerge when the pot is moved. Allow the top inch of compost to dry; use yellow sticky traps; drench with Bti solution to kill larvae.