Troubleshooting
Chinese Hemlock problems — and how to fix them
Chinese Hemlock (Tsuga chinensis) 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.
Phytophthora root rot in wet soil
Waterlogged conditions, particularly in winter, lead to Phytophthora root rot causing wilting and decline. Ensure excellent drainage; plant on a slight slope or in raised beds in heavy soils.
Spider mites in hot, dry conditions
In hot summers with low humidity, spider mite populations can build rapidly on the fine foliage, causing greyish stippling. Increase irrigation and humidity around the plant; apply horticultural oil or insecticidal soap in early summer.
Wind and sun scorch on exposed sites
Young specimens with their finely textured foliage are susceptible to desiccating winds and intense sun. Plant in a sheltered position and provide temporary windbreak protection for the first two winters after planting.
Prevent chinese hemlock problems before they start
Most chinese hemlock issues are care-mismatch, not bad luck. Dial in the basics:
Chinese Hemlock problems — FAQ
Why is my chinese hemlock phytophthora root rot in wet soil?
Waterlogged conditions, particularly in winter, lead to Phytophthora root rot causing wilting and decline. Ensure excellent drainage; plant on a slight slope or in raised beds in heavy soils.
Why is my chinese hemlock spider mites in hot, dry conditions?
In hot summers with low humidity, spider mite populations can build rapidly on the fine foliage, causing greyish stippling. Increase irrigation and humidity around the plant; apply horticultural oil or insecticidal soap in early summer.
Why is my chinese hemlock wind and sun scorch on exposed sites?
Young specimens with their finely textured foliage are susceptible to desiccating winds and intense sun. Plant in a sheltered position and provide temporary windbreak protection for the first two winters after planting.