Troubleshooting
Water Speedwell problems — and how to fix them
Water Speedwell (Veronica anagallis-aquatica) 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.
Self-seeding becoming weedy
Water Speedwell self-seeds prolifically and can colonise beyond its intended planting area. Deadhead spent flower racemes before seed sets if spread needs to be controlled in a managed pond or garden.
Powdery mildew in stagnant air
Plants in warm, sheltered positions with poor air circulation may develop powdery mildew on leaves in late summer. Thin out congested growth to improve airflow; the plant typically regenerates healthy growth quickly.
Frost die-back of top growth
Top growth often dies back in hard winters, but the rootstock re-sprouts reliably in spring. Self-sown seedlings also overwinter and fill gaps. No protection is normally needed in UK climates.
Prevent water speedwell problems before they start
Most water speedwell issues are care-mismatch, not bad luck. Dial in the basics:
Water Speedwell problems — FAQ
Why is my water speedwell self-seeding becoming weedy?
Water Speedwell self-seeds prolifically and can colonise beyond its intended planting area. Deadhead spent flower racemes before seed sets if spread needs to be controlled in a managed pond or garden.
Why is my water speedwell powdery mildew in stagnant air?
Plants in warm, sheltered positions with poor air circulation may develop powdery mildew on leaves in late summer. Thin out congested growth to improve airflow; the plant typically regenerates healthy growth quickly.
Why is my water speedwell frost die-back of top growth?
Top growth often dies back in hard winters, but the rootstock re-sprouts reliably in spring. Self-sown seedlings also overwinter and fill gaps. No protection is normally needed in UK climates.