Troubleshooting
Catlin's Giant Bugle problems — and how to fix them
Catlin's Giant Bugle (Ajuga reptans 'Catlin's Giant') 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
The most common problem, especially in poorly drained or overly dense plantings. Improve air circulation by thinning crowded colonies in autumn and ensure the planting site drains freely. Avoid overhead watering in cool, wet weather.
Powdery mildew
Can appear in humid, shaded conditions with poor airflow. Space plants adequately (30–40 cm apart) and remove affected leaves promptly. A dilute neem oil or potassium bicarbonate spray controls mild outbreaks.
Invasive spreading
Runners root readily and can spread beyond desired areas. Edge planting beds regularly in spring and autumn with a spade to contain the colony. Avoid planting adjacent to lawn where it will outcompete grass.
Prevent catlin's giant bugle problems before they start
Most catlin's giant bugle issues are care-mismatch, not bad luck. Dial in the basics:
Catlin's Giant Bugle problems — FAQ
Why is my catlin's giant bugle crown rot?
The most common problem, especially in poorly drained or overly dense plantings. Improve air circulation by thinning crowded colonies in autumn and ensure the planting site drains freely. Avoid overhead watering in cool, wet weather.
Why is my catlin's giant bugle powdery mildew?
Can appear in humid, shaded conditions with poor airflow. Space plants adequately (30–40 cm apart) and remove affected leaves promptly. A dilute neem oil or potassium bicarbonate spray controls mild outbreaks.
Why is my catlin's giant bugle invasive spreading?
Runners root readily and can spread beyond desired areas. Edge planting beds regularly in spring and autumn with a spade to contain the colony. Avoid planting adjacent to lawn where it will outcompete grass.