Troubleshooting
Heather problems — and how to fix them
Heather (Calluna vulgaris) 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.
Soil pH too high (chlorosis)
Yellowing foliage with green veins indicates iron deficiency caused by alkaline soil. Apply sulphur dust to lower pH, switch to rainwater irrigation, and treat with sequestered iron chelate feed.
Leggy or open growth
Caused by insufficient light or failure to prune. Trim lightly immediately after flowering each year with shears, removing spent flower heads but never cutting back into bare old wood, which does not regenerate.
Phytophthora root rot
Sudden wilting and blackening of stems in wet, poorly drained conditions. Improve drainage, avoid overwatering, and do not replant heathers in the same spot. No effective chemical treatment once established.
Prevent heather problems before they start
Most heather issues are care-mismatch, not bad luck. Dial in the basics:
Heather problems — FAQ
Why is my heather soil ph too high (chlorosis)?
Yellowing foliage with green veins indicates iron deficiency caused by alkaline soil. Apply sulphur dust to lower pH, switch to rainwater irrigation, and treat with sequestered iron chelate feed.
Why is my heather leggy or open growth?
Caused by insufficient light or failure to prune. Trim lightly immediately after flowering each year with shears, removing spent flower heads but never cutting back into bare old wood, which does not regenerate.
Why is my heather phytophthora root rot?
Sudden wilting and blackening of stems in wet, poorly drained conditions. Improve drainage, avoid overwatering, and do not replant heathers in the same spot. No effective chemical treatment once established.