Troubleshooting
Red Clockvine problems — and how to fix them
Red Clockvine (Thunbergia coccinea) is generally forgiving once you match its basics, but a few issues come up again and again. Here is what each one looks like, why it happens, and the fix.
Poor flowering from over-pruning
T. coccinea blooms on the previous year's wood. Cutting back hard in autumn removes next season's flower buds. Prune lightly only after the flowering period has ended, removing dead or crossing stems.
Aphids and mealybugs
Soft new shoot growth and flower buds attract aphid and mealybug colonies, especially under glass. Treat with insecticidal soap or neem oil spray, and introduce biological controls such as Aphidius parasitic wasps in enclosed glasshouses.
Cold damage under glass
Even brief temperature drops below 10 °C cause leaf yellowing and stem dieback. Maintain a minimum night temperature of 13–15 °C in winter and keep the plant away from draughty vents or cold glass.
Prevent red clockvine problems before they start
Most red clockvine issues are care-mismatch, not bad luck. Dial in the basics:
Red Clockvine problems — FAQ
Why is my red clockvine poor flowering from over-pruning?
T. coccinea blooms on the previous year's wood. Cutting back hard in autumn removes next season's flower buds. Prune lightly only after the flowering period has ended, removing dead or crossing stems.
Why is my red clockvine aphids and mealybugs?
Soft new shoot growth and flower buds attract aphid and mealybug colonies, especially under glass. Treat with insecticidal soap or neem oil spray, and introduce biological controls such as Aphidius parasitic wasps in enclosed glasshouses.
Why is my red clockvine cold damage under glass?
Even brief temperature drops below 10 °C cause leaf yellowing and stem dieback. Maintain a minimum night temperature of 13–15 °C in winter and keep the plant away from draughty vents or cold glass.