Stem Blight of Catharanthus rosea (V. rosea, Vinca minor (Periwinkle) and Vinca major (big-leaf or variegated) is caused by the fungus Phoma exigua. Symptoms consist of rapidly expanding, dark brown to black, girdling lesions on stems at the soil line which result in dieback. Stem lesions expand rapidly, spread to the base of new shoots, and cause wilting, browning, and plant death. The pathogen is widespread and the disease is potentially destructive wherever these plants are grown. Stem blight may be so severe that plantings cannot be maintained and must be replaced. Newly planted beds are most susceptible.