Troubleshooting
Heucherella Stoplight problems — and how to fix them
Heucherella Stoplight (Heucherella 'Stoplight') 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.
Leaf scorch / bleaching
The bright thin leaves burn in strong afternoon sun or dry soil. Site in partial shade with even moisture and mulch.
Crown rot
Cold, wet, poorly drained soil rots the crown over winter. Plant in well-drained humus-rich soil and keep water from pooling at the base.
Frost heave
The shallow crown can be pushed up by winter freeze-thaw cycles. Apply winter mulch and press heaved plants back into the soil in spring.
Powdery mildew
Crowded, humid, still-air conditions encourage mildew on the leaves. Improve spacing and airflow and water at soil level.
Prevent heucherella stoplight problems before they start
Most heucherella stoplight issues are care-mismatch, not bad luck. Dial in the basics:
Looking for heucherella stoplight in general rather than its problems? Read the full heucherella stoplight care guide — light, water, soil and feeding.
Heucherella Stoplight problems — FAQ
Why is my heucherella stoplight leaf scorch / bleaching?
The bright thin leaves burn in strong afternoon sun or dry soil. Site in partial shade with even moisture and mulch.
Why is my heucherella stoplight crown rot?
Cold, wet, poorly drained soil rots the crown over winter. Plant in well-drained humus-rich soil and keep water from pooling at the base.
Why is my heucherella stoplight frost heave?
The shallow crown can be pushed up by winter freeze-thaw cycles. Apply winter mulch and press heaved plants back into the soil in spring.
Why is my heucherella stoplight powdery mildew?
Crowded, humid, still-air conditions encourage mildew on the leaves. Improve spacing and airflow and water at soil level.