Troubleshooting
Comb Speedwell problems — and how to fix them
Comb Speedwell (Veronica pectinata) 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.
Winter wet rot
The primary threat in cool, wet climates. Prolonged winter moisture on the mat causes crown and stem rot. Ensure extremely sharp drainage; plant on a slope or in a raised bed, and avoid mulching over the crown.
Downy mildew in wet springs
Yellow patches on the upper leaf surface with grey-purple fuzz beneath indicate downy mildew. Improve air circulation, avoid overhead watering, and remove affected growth. Susceptibility increases in cool, wet seasons.
Loss of silver colouration in shade or rich soil
The attractive silver-grey leaf texture is sun- and stress-dependent. Plants moved to shade or grown in fertile soil rapidly turn plain green and lose ornamental appeal. Restore by moving to a sunnier, leaner site.
Prevent comb speedwell problems before they start
Most comb speedwell issues are care-mismatch, not bad luck. Dial in the basics:
Comb Speedwell problems — FAQ
Why is my comb speedwell winter wet rot?
The primary threat in cool, wet climates. Prolonged winter moisture on the mat causes crown and stem rot. Ensure extremely sharp drainage; plant on a slope or in a raised bed, and avoid mulching over the crown.
Why is my comb speedwell downy mildew in wet springs?
Yellow patches on the upper leaf surface with grey-purple fuzz beneath indicate downy mildew. Improve air circulation, avoid overhead watering, and remove affected growth. Susceptibility increases in cool, wet seasons.
Why is my comb speedwell loss of silver colouration in shade or rich soil?
The attractive silver-grey leaf texture is sun- and stress-dependent. Plants moved to shade or grown in fertile soil rapidly turn plain green and lose ornamental appeal. Restore by moving to a sunnier, leaner site.