Overwintering guide
How to overwinter begonia 'black coffee'
Winter watering
Cut watering right back — begonia 'black coffee' uses far less while growth slows, and cold, wet compost is the usual cause of winter root rot. Stop feeding until spring.
The mistake that kills begonia 'black coffee' in winter
Watering on the same schedule as summer. In winter that keeps the roots sodden while the plant is barely drinking, and begonia 'black coffee' rots from the base.
More begonia 'black coffee' care
Overwintering begonia 'black coffee' — FAQ
Does begonia 'black coffee' need to come indoors for winter?
Begonia 'Black Coffee' is hardy to roughly USDA zone 10 — winter lows around -1°C. That means it will not survive frost and needs to come inside. Begonia 'Black Coffee' is frost-tender, so overwintering means bringing it inside and letting it rest rather than pushing it to grow. Move it indoors well before the first frost, give it the brightest spot you have (light levels indoors drop sharply in winter), and keep it away from both cold window glass and hot radiators — the swing between the two does more damage than the cold itself.
When should I move begonia 'black coffee' for winter?
Bring indoors when nights start dropping below about 10°C, ahead of the first frost.
How often should I water begonia 'black coffee' in winter?
Cut watering right back — begonia 'black coffee' uses far less while growth slows, and cold, wet compost is the usual cause of winter root rot. Stop feeding until spring.
What kills begonia 'black coffee' over winter?
Watering on the same schedule as summer. In winter that keeps the roots sodden while the plant is barely drinking, and begonia 'black coffee' rots from the base.