Troubleshooting
Blue Oat Grass problems — and how to fix them
Blue Oat Grass (Helictotrichon sempervirens) 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.
Rust disease
Orange rust pustules can mar the blue foliage in humid or crowded conditions. Improve airflow, avoid overhead watering, and remove affected leaves; site in full sun.
Crown rot in wet soil
Heavy or winter-wet ground rots the base. Plant in sharp drainage, on a raised or gritty site, and avoid waterlogged positions.
Loss of blue colour
Shade or rich soil turns the foliage greener and looser. Grow in full sun on lean ground for the best steel-blue tone and tight form.
Tatty old foliage
Dead blades accumulate over time. Comb out brown leaves by hand in spring rather than cutting this evergreen grass back hard.
Prevent blue oat grass problems before they start
Most blue oat grass issues are care-mismatch, not bad luck. Dial in the basics:
Looking for blue oat grass in general rather than its problems? Read the full blue oat grass care guide — light, water, soil and feeding.
Blue Oat Grass problems — FAQ
Why is my blue oat grass rust disease?
Orange rust pustules can mar the blue foliage in humid or crowded conditions. Improve airflow, avoid overhead watering, and remove affected leaves; site in full sun.
Why is my blue oat grass crown rot in wet soil?
Heavy or winter-wet ground rots the base. Plant in sharp drainage, on a raised or gritty site, and avoid waterlogged positions.
Why is my blue oat grass loss of blue colour?
Shade or rich soil turns the foliage greener and looser. Grow in full sun on lean ground for the best steel-blue tone and tight form.
Why is my blue oat grass tatty old foliage?
Dead blades accumulate over time. Comb out brown leaves by hand in spring rather than cutting this evergreen grass back hard.