Troubleshooting
Emerald Green Arborvitae problems — and how to fix them
Emerald Green Arborvitae (Thuja occidentalis 'Smaragd') 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.
Bagworms
Spindle-shaped bags on foliage in summer; hand-pick in autumn/winter or treat with Bt in spring.
Spider mites in drought
Yellow stippling on foliage in hot, dry conditions; water well and treat with insecticidal soap.
Root rot
Overwatering or poorly drained soil; improve drainage and reduce watering frequency.
Tip dieback
Cold winters or ice damage can cause tip browning; prune dead tips in spring and the plant usually recovers fully.
Prevent emerald green arborvitae problems before they start
Most emerald green arborvitae issues are care-mismatch, not bad luck. Dial in the basics:
Emerald Green Arborvitae problems — FAQ
Why is my emerald green arborvitae bagworms?
Spindle-shaped bags on foliage in summer; hand-pick in autumn/winter or treat with Bt in spring.
Why is my emerald green arborvitae spider mites in drought?
Yellow stippling on foliage in hot, dry conditions; water well and treat with insecticidal soap.
Why is my emerald green arborvitae root rot?
Overwatering or poorly drained soil; improve drainage and reduce watering frequency.
Why is my emerald green arborvitae tip dieback?
Cold winters or ice damage can cause tip browning; prune dead tips in spring and the plant usually recovers fully.