What's eating my begonia 'sachsen'?

Begonia rex-cultorum 'Sachsen' is a Rex begonia grown for its ornate foliage indoors. Rex begonias are particularly attractive to mealybugs and spider mites. The textured, deeply colored leaves can hide early infestations, so inspect crevices carefully. Avoid overhead watering to reduce the powdery mildew risk common across Rex types.

White waxy masses in the grooves of textured leaves and at petiole bases; honeydew and sooty mold on the ornamental foliage. Remove with isopropyl alcohol on a swab; spray with neem oil or insecticidal soap every 7–10 days; repeat until clear.

Pale stippling dulls the vibrant leaf patterns; fine webbing on undersides; leaves may curl and dry at edges in dry indoor air. Boost humidity; wipe leaves gently with a damp cloth; apply neem oil or miticide spray on a weekly schedule for 3–4 weeks.

Silver streaks and distorted new leaves; dark frass deposits; adult thrips visible when leaves are shaken over white paper. Remove damaged foliage; apply spinosad or insecticidal soap spray; use sticky blue traps; repeat treatment every 5–7 days.

Notched leaf margins from adult feeding at night; larvae in soil eat rhizomes, causing sudden plant collapse. Drench soil with pathogenic nematodes (Steinernema kraussei) in autumn; inspect roots when repotting; use vine weevil traps around pots.