Pest identification
What's eating my iron cross begonia?
Mealybugs
Signs: White cottony clusters between leaves and along petioles; stunted, sticky, sooty growth
Control: Remove with alcohol swabs; follow with insecticidal soap spray; repeat weekly
Vine weevil
Signs: Grubs eat rhizomes underground; plant suddenly wilts and collapses despite adequate watering
Control: Apply nematodes (Steinernema kraussei or S. carpocapsae) to the soil in spring; check roots when repotting
Fungus gnats
Signs: Root damage from larvae in moist compost; adults hover around the plant
Control: Allow soil surface to dry before watering; use sticky yellow traps and a Bti soil drench
Keep iron cross begonia pest-free
Healthy plants resist pests best. Get the basics right:
Iron Cross Begonia pests — FAQ
What is eating my iron cross begonia?
Iron Cross Begonia is most commonly attacked by mealybugs, which exploit its textured, hairy leaves. Vine weevil larvae can devastate the rhizomes in UK and US gardens and indoor pots alike. Fungus gnats breed in the moist soil this begonia prefers. Powdery mildew and botrytis are additional threats in poor air circulation.
How do I get rid of mealybugs on iron cross begonia?
White cottony clusters between leaves and along petioles; stunted, sticky, sooty growth Remove with alcohol swabs; follow with insecticidal soap spray; repeat weekly
How do I get rid of vine weevil on iron cross begonia?
Grubs eat rhizomes underground; plant suddenly wilts and collapses despite adequate watering Apply nematodes (Steinernema kraussei or S. carpocapsae) to the soil in spring; check roots when repotting
How do I get rid of fungus gnats on iron cross begonia?
Root damage from larvae in moist compost; adults hover around the plant Allow soil surface to dry before watering; use sticky yellow traps and a Bti soil drench