Troubleshooting
Black Fang Begonia problems — and how to fix them
Black Fang Begonia (Begonia 'Black Fang') 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.
Rhizome rot from overwatering
The creeping rhizome is the most vulnerable part of this plant; if the compost stays wet for extended periods the rhizome turns soft and brown — repot immediately into dry compost, cutting away affected sections with a clean blade.
Powdery mildew
Dark-leaved begonias are susceptible to powdery mildew, particularly in low-light, stagnant-air conditions; improve ventilation, avoid wetting foliage, and treat with a bicarbonate-based or sulphur fungicide at the first sign of white powdery coating.
Prevent black fang begonia problems before they start
Most black fang begonia issues are care-mismatch, not bad luck. Dial in the basics:
Black Fang Begonia problems — FAQ
Why is my black fang begonia rhizome rot from overwatering?
The creeping rhizome is the most vulnerable part of this plant; if the compost stays wet for extended periods the rhizome turns soft and brown — repot immediately into dry compost, cutting away affected sections with a clean blade.
Why is my black fang begonia powdery mildew?
Dark-leaved begonias are susceptible to powdery mildew, particularly in low-light, stagnant-air conditions; improve ventilation, avoid wetting foliage, and treat with a bicarbonate-based or sulphur fungicide at the first sign of white powdery coating.