Growli

Troubleshooting

Caryopteris x clandonensis 'Dark Knight' problems — and how to fix them

Caryopteris x clandonensis 'Dark Knight' (Caryopteris x clandonensis 'Dark Knight') 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.

Root rot in wet soil

Poorly drained or winter-wet ground rots the roots. Plant high in gritty, free-draining soil.

Powdery mildew

White coating on leaves in humid or crowded conditions. Space plants for airflow and site in full sun.

Sparse flowering

Insufficient sun or no spring pruning yields fewer blooms. Give full sun and cut back hard each spring.

Winter stem dieback

Top growth can die back in cold winters. Cut to a low framework in spring; it regrows and flowers on new wood.

Prevent caryopteris x clandonensis 'dark knight' problems before they start

Most caryopteris x clandonensis 'dark knight' issues are care-mismatch, not bad luck. Dial in the basics:

Looking for caryopteris x clandonensis 'dark knight' in general rather than its problems? Read the full caryopteris x clandonensis 'dark knight' care guide — light, water, soil and feeding.

Caryopteris x clandonensis 'Dark Knight' problems — FAQ

Why is my caryopteris x clandonensis 'dark knight' root rot in wet soil?

Poorly drained or winter-wet ground rots the roots. Plant high in gritty, free-draining soil.

Why is my caryopteris x clandonensis 'dark knight' powdery mildew?

White coating on leaves in humid or crowded conditions. Space plants for airflow and site in full sun.

Why is my caryopteris x clandonensis 'dark knight' sparse flowering?

Insufficient sun or no spring pruning yields fewer blooms. Give full sun and cut back hard each spring.

Why is my caryopteris x clandonensis 'dark knight' winter stem dieback?

Top growth can die back in cold winters. Cut to a low framework in spring; it regrows and flowers on new wood.