Troubleshooting
Russian Arborvitae problems — and how to fix them
Russian Arborvitae (Microbiota decussata) 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.
Foliage scorch in hot, dry sites
Prolonged heat combined with dry soil causes brown, crispy foliage, particularly on the tips. Site in a position with afternoon shade in USDA zones 7–8, mulch generously, and provide supplemental irrigation during summer heat waves.
Root rot in waterlogged soil
Though cold-hardy, Microbiota is not tolerant of waterlogged soils. Plant on well-drained slopes or raised areas; amend heavy clay with grit before planting. Persistent wet roots lead to Phytophthora infection and sudden browning.
Spider mites in dry conditions
Red spider mites colonise foliage during hot, dry spells, causing a dusty, bronzed appearance. Increase humidity by watering in the evening, wash foliage with a strong jet of water, or apply an insecticidal soap spray as needed.
Prevent russian arborvitae problems before they start
Most russian arborvitae issues are care-mismatch, not bad luck. Dial in the basics:
Looking for russian arborvitae in general rather than its problems? Read the full russian arborvitae care guide — light, water, soil and feeding.
Russian Arborvitae problems — FAQ
Why is my russian arborvitae foliage scorch in hot, dry sites?
Prolonged heat combined with dry soil causes brown, crispy foliage, particularly on the tips. Site in a position with afternoon shade in USDA zones 7–8, mulch generously, and provide supplemental irrigation during summer heat waves.
Why is my russian arborvitae root rot in waterlogged soil?
Though cold-hardy, Microbiota is not tolerant of waterlogged soils. Plant on well-drained slopes or raised areas; amend heavy clay with grit before planting. Persistent wet roots lead to Phytophthora infection and sudden browning.
Why is my russian arborvitae spider mites in dry conditions?
Red spider mites colonise foliage during hot, dry spells, causing a dusty, bronzed appearance. Increase humidity by watering in the evening, wash foliage with a strong jet of water, or apply an insecticidal soap spray as needed.