Troubleshooting
Three-Part Begonia problems — and how to fix them
Three-Part Begonia (Begonia tripartita) is generally low-drama, but a few issues come up again and again. Here is what each one looks like, why it happens, and the fix.
Botrytis (grey mould)
Fluffy grey mould appears on leaves and stems in cool, damp, poorly ventilated conditions. Remove affected tissue promptly, improve air circulation, and reduce overhead moisture.
Vine weevil
Larvae feed on the fibrous roots and can kill the plant before adult notching on leaf margins is noticed; check roots when repotting and treat with a vine-weevil nematode drench in spring or autumn.
Prevent three-part begonia problems before they start
Most three-part begonia issues are care-mismatch, not bad luck. Dial in the basics:
Looking for three-part begonia in general rather than its problems? Read the full three-part begonia care guide — light, water, soil and feeding.
Three-Part Begonia problems — FAQ
Why is my three-part begonia botrytis (grey mould)?
Fluffy grey mould appears on leaves and stems in cool, damp, poorly ventilated conditions. Remove affected tissue promptly, improve air circulation, and reduce overhead moisture.
Why is my three-part begonia vine weevil?
Larvae feed on the fibrous roots and can kill the plant before adult notching on leaf margins is noticed; check roots when repotting and treat with a vine-weevil nematode drench in spring or autumn.