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. The fungus persists indefinitely in moist soil and plant debris and can be transmitted via infected plants shipped from propagating nurseries. P. exigua is favored by the cool, wet weather of spring and can also occur in the fall when soil moisture is high. Start with disease free cuttings. Avoid overwatering. Remove and destroy infected plants and plant debris. Drench with thiophante-methyl (Cleary’s 3336), mancozeb (Protect T/O), pyraclostrobin plus boscalid (Pageant),or copper containing fungicides (Champ).