Troubleshooting
Common Bugle problems — and how to fix them
Common Bugle (Ajuga reptans) 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.
Crown rot (Phytophthora root rot)
The leading cause of patch dieback in Ajuga, especially in poorly drained, warm, humid conditions. Affected plants collapse and turn brown from the centre outward. Improve drainage, avoid overhead watering, thin dense mats for airflow, and remove affected patches promptly. There is no chemical cure once established.
Invasive spreading
Ajuga reptans spreads vigorously by stolons and can become weedy, particularly in lawn areas. Edge beds regularly with a sharp spade, pull excess stolons, and site where spreading is welcome or install an edging barrier to contain the mat.
Powdery mildew
White powdery coating appears on foliage in warm, dry conditions with poor air circulation. Thin overcrowded mats and water at the base rather than overhead. Treat with a bicarbonate spray or neem oil at early stages. Choose resistant cultivars where mildew is a recurrent problem.
Prevent common bugle problems before they start
Most common bugle issues are care-mismatch, not bad luck. Dial in the basics:
Common Bugle problems — FAQ
Why is my common bugle crown rot (phytophthora root rot)?
The leading cause of patch dieback in Ajuga, especially in poorly drained, warm, humid conditions. Affected plants collapse and turn brown from the centre outward. Improve drainage, avoid overhead watering, thin dense mats for airflow, and remove affected patches promptly. There is no chemical cure once established.
Why is my common bugle invasive spreading?
Ajuga reptans spreads vigorously by stolons and can become weedy, particularly in lawn areas. Edge beds regularly with a sharp spade, pull excess stolons, and site where spreading is welcome or install an edging barrier to contain the mat.
Why is my common bugle powdery mildew?
White powdery coating appears on foliage in warm, dry conditions with poor air circulation. Thin overcrowded mats and water at the base rather than overhead. Treat with a bicarbonate spray or neem oil at early stages. Choose resistant cultivars where mildew is a recurrent problem.