Troubleshooting
Prostrate Speedwell problems — and how to fix them
Prostrate Speedwell (Veronica prostrata) 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.
Powdery mildew
White powdery deposits appear on leaves in warm, humid conditions with poor air circulation. Thin the mat by cutting back after flowering to improve airflow. A preventive copper-based fungicide can be applied in prone areas.
Overrunning neighbouring plants
The vigorous spreading mat can engulf small, slow-growing rock garden plants. Trim back the edges twice a year (after flowering and in early autumn) to keep it within bounds.
Failure to rebloom after warm winters
Veronica prostrata needs cool winter temperatures to set flower buds. Plants in frost-free microclimates or unusually warm winters may produce little or no spring bloom. Ensure an open, exposed position.
Prevent prostrate speedwell problems before they start
Most prostrate speedwell issues are care-mismatch, not bad luck. Dial in the basics:
Prostrate Speedwell problems — FAQ
Why is my prostrate speedwell powdery mildew?
White powdery deposits appear on leaves in warm, humid conditions with poor air circulation. Thin the mat by cutting back after flowering to improve airflow. A preventive copper-based fungicide can be applied in prone areas.
Why is my prostrate speedwell overrunning neighbouring plants?
The vigorous spreading mat can engulf small, slow-growing rock garden plants. Trim back the edges twice a year (after flowering and in early autumn) to keep it within bounds.
Why is my prostrate speedwell failure to rebloom after warm winters?
Veronica prostrata needs cool winter temperatures to set flower buds. Plants in frost-free microclimates or unusually warm winters may produce little or no spring bloom. Ensure an open, exposed position.