Red twig dogwood leaves disintegrating
Hello! We planted variegated red twig dogwoods in full sun this past spring. In early August, the leaves started getting purplish-brown/black spots, which spread and got bigger, then the leaves started disintegrating on the branches. New growth leaves also developed the spots. I suspect a fungus, but would like know what can be done to avoid plant decline, and/or if (if a fungus) will spread to other plants. Two pictures are from today, one is from early August when I first noticed the problem. Thanks very much,
Red twig dogwood grows best in full sun to part shade and are adaptable to a wide range of soil conditions. They can be susceptible to a variety of pest and fungal issues such as leaf spots and twig blights (stem cankers). The leaf spots may be more of an issue in wet weather which has been abundant this season.
All you can do is rake any fallen leaves and prune unhealthy stems back to healthy tissue. Make sure mulch is not thicker than several inches and keep away from the base of the stems. Prune if needed to provide good air circulation. It is possible you may not have an issue next season.
Monitor the growth next season and you can send us photos if you notice additional symptoms. Here is more on red twig dogwood from NC State and Va Tech.