Troubleshooting
Spiked speedwell problems — and how to fix them
Spiked speedwell (Veronica spicata) 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 mildew on leaves and stems is the most common problem, appearing in warm, humid weather or during drought stress. Improve air circulation, avoid water stress, and remove affected leaves promptly. Treat with a sulfur-based or potassium bicarbonate fungicide if widespread.
Downy mildew and root rot in wet soils
In poorly drained or waterlogged soils, Veronica spicata is susceptible to root and crown rots. Ensure well-drained planting sites; incorporate grit into heavy soils. Avoid overhead irrigation and waterlogged conditions in winter.
Short flower spikes from poor light or rich soil
Plants in too much shade or over-fertilised ground produce taller, lax stems with few flowers. Ensure full sun and lean soil. Divide clumps every 3–4 years in spring to maintain vigour; old congested clumps flower less freely.
Prevent spiked speedwell problems before they start
Most spiked speedwell issues are care-mismatch, not bad luck. Dial in the basics:
Looking for spiked speedwell in general rather than its problems? Read the full spiked speedwell care guide — light, water, soil and feeding.
Spiked speedwell problems — FAQ
Why is my spiked speedwell powdery mildew?
White powdery mildew on leaves and stems is the most common problem, appearing in warm, humid weather or during drought stress. Improve air circulation, avoid water stress, and remove affected leaves promptly. Treat with a sulfur-based or potassium bicarbonate fungicide if widespread.
Why is my spiked speedwell downy mildew and root rot in wet soils?
In poorly drained or waterlogged soils, Veronica spicata is susceptible to root and crown rots. Ensure well-drained planting sites; incorporate grit into heavy soils. Avoid overhead irrigation and waterlogged conditions in winter.
Why is my spiked speedwell short flower spikes from poor light or rich soil?
Plants in too much shade or over-fertilised ground produce taller, lax stems with few flowers. Ensure full sun and lean soil. Divide clumps every 3–4 years in spring to maintain vigour; old congested clumps flower less freely.