Question From: S. Browne - Grove City, Pennsylvania, United States
Q: watanabe viburnum: late spring ; tips (really more than just the tips) of many of the leaves are turning reddish-brown. Is it a pH problem? A nutrient problem? A moisture problem?
I believe the plant is suffering from the fungus downy mildew. Treat it with a fungicide labeled for that plant and that disease. Be sure to spray the undersides of the leaves as well as the top. Thining out the plant by pruning will increase circulation. Be sure to dispose of all fallen leaves and twigs. Best And Happy Yardening, Nancy