Q: We have a steep hill that is covered with mature Japanese Pachysandra that is dying. It is under a large tulip tree. This groundcover was healthy for more than twenty years. During the last couple of years the leaves have turned yellow then the tips turn brown and curl up. The plant then dies. What is going on and how can we correct this problem?
A: This is a common problem in old Japanese Pachysandra (Pachysandra terminalis) beds. You are seeing the symptoms of a fungal disease called Volutella blight (Volutella pachysandricola). This opportunistic pathogen attacks Japanese Pachysandra that has become weakened by drought, poor site conditions, and/or wounding. Volutella blight is most severe in overgrown plantings and is also often associated with scale insect infestations. All symptomatic plant material should be pulled and put in the trash. Do not compost it.
It is difficult to control this disease effectively with fungicides. Once lesions are visible on the stems and leaves, it is too late for fungicides to be effective. You can try to manage the disease by renovating your planting bed periodically. Remove some of the plants to create thinner, less dense growth and allow for more air circulation. Water (only in the morning) during periods of drought to reduce plant stress. Rake out leaves in the fall. Anything you can do to minimize overnight moisture can help.
Even with good sanitation and care, Volutella blight is difficult to control completely. Consider replacing your Japanese Pachysandra with native plants. Pachysandra terminalis is invasive and no longer recommend as a groundcover. Native ferns such as hay-scented ferns and common ladyferns are two tough plants that will grow in partial shade. They are also deer resistant. Additional groundcovers are listed on the Home and Garden Information Center website.
By Christa Carignan, Coordinator, University of Maryland Extension Home & Garden Information Center
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