Viburnum Downy Mildew

Figure 2. Typical bronzing of the upper leaf surface of Viburnum odoratissimum ‘Awabuki’ as a result of downy mildew. Credits: A.J. Palmateer, UF/IFAS

Downy mildew on viburnum is currently a serious concern throughout Florida. Winters in south Florida combine high humidity with cool nights, creating ideal conditions for disease development. Downy mildews are caused by several different species that tend to be host specific. Plasmopara vibruni is the pathogen that affects viburnum. This five-page fact sheet describes the hosts, symptoms, and management practices for Viburnum Downy Mildew.
Written by A. J. Palmateer and published by the Plant Pathology Department.