Troubleshooting
Cornish heath problems — and how to fix them
Cornish heath (Erica vagans) 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.
Woody dieback without pruning
Erica vagans grows vigorously and becomes leggy and woody without annual trimming. Clip spent flower stems back to green growth each October or November after blooming ends. Unlike some heathers, it can tolerate being cut back slightly harder but still avoid old woody stems.
Lime-induced chlorosis
Though more lime-tolerant than most heathers, plants in alkaline soils above pH 7.5 will show yellow foliage from iron deficiency. Apply sequestered iron and mulch with ericaceous bark. In very alkaline soils, container culture with ericaceous compost is more reliable.
Phytophthora root rot
Persistently waterlogged soil triggers rapid wilting and root death. Ensure adequate drainage, especially on heavy clay. Raise beds if necessary. Remove and destroy infected plants — there is no effective chemical cure available to home gardeners.
Prevent cornish heath problems before they start
Most cornish heath issues are care-mismatch, not bad luck. Dial in the basics:
Cornish heath problems — FAQ
Why is my cornish heath woody dieback without pruning?
Erica vagans grows vigorously and becomes leggy and woody without annual trimming. Clip spent flower stems back to green growth each October or November after blooming ends. Unlike some heathers, it can tolerate being cut back slightly harder but still avoid old woody stems.
Why is my cornish heath lime-induced chlorosis?
Though more lime-tolerant than most heathers, plants in alkaline soils above pH 7.5 will show yellow foliage from iron deficiency. Apply sequestered iron and mulch with ericaceous bark. In very alkaline soils, container culture with ericaceous compost is more reliable.
Why is my cornish heath phytophthora root rot?
Persistently waterlogged soil triggers rapid wilting and root death. Ensure adequate drainage, especially on heavy clay. Raise beds if necessary. Remove and destroy infected plants — there is no effective chemical cure available to home gardeners.