Once infected, the fruit cannot be treated. Effective control of the disease can be obtained by spraying an appropriate fungicide in the autumn after the leaves have fallen, or in the spring before buds begin to swell. Recommended fungicides include chlorothalonil, lime-sulfur, Bordeaux mixture, or a fixed copper fungicide. Vinca canker and dieback Vinca canker and dieback is caused by a species of the fungus Phoma . The disease typically causes shoot tips, leaves, or stems to wilt and blacken.
Plants become thin and weak.
The disease is usually worse on plants under environmental stress. To control the disease, remove infected plants or prune out diseased plant parts. Improve vigor with fertilization and watering. Mulching may be beneficial. Avoid overhead watering.