Boxwood blight in commercial nursery production

Boxwood blight is a fungal disease caused by Calonectria pseudonaviculata that thrives in cool, humid conditions and spreads through water, tools and infected plant material, leading to leaf spots, stem lesions and rapid defoliation.

Boxwood blight uncovered: From infection to detection

Boxwood blight is a destructive fungal disease affecting boxwood in commercial nurseries that spreads quickly under humid, moderate conditions, causing leaf spots, stem lesions and rapid defoliation.

Luisa Santamaria | Dec 2025 | OSU Extension Catalog

Boxwood Blight in commercial nursery production

Boxwood blight, caused by the fungus Calonectria pseudonaviculata, leads to stem lesions, leaf spots and defoliation. It spreads in wet, humid conditions and through contaminated plants, soil or equipment, so experts ...

Luisa Santamaria | Sep 2025 | OSU Extension Catalog

Beware of boxwood blight!

Useful information for homeowners, Master Gardeners and landscapers about boxwood blight disease: its symptoms, sanitation measures when it is discovered on a property, and preventive measures.

Cassie Bouska, Jay W. Pscheidt | Jun 2024 | OSU Extension Catalog Peer reviewed (Orange level)

Jan 2026

Author

Luisa Santamaria

Nursery Pathology Specialist, Bilingual Educator

Hand holding a diseased plant with person looking on

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