Question From: New Hampshire, United States
Q: My snow mound spirea shrubs are getting black spots on the leaves and they start to drop off. This has happened the same time the last several years however the foliage always comes in healthy early in the season.
As the information in Yardener.com reads - your shrubs have a fungal disease. As it has progressed to the point they are losing leaves, they should be sprayed with a fungicide every 7 to 10 days. Be sure to hit the undersides of the leaves. Be fastidious about cleaning up dead refuse under the shrubs, especially in spring. Black spot on spirea is rarely serious, but when the leaves drop it should be treated. Bayer Disease Control for Roses, Flowers and Shrubs would be a good choice. Next spring, begin spraying in May, before the plants show signs of disease. The spots will not go away but new leaves should be clear.Water at the base of the shrubs. Do not use chemical fertilizers, Espoma Plant Tone in late fall will work nicely. Best And Happy Yardening, Nancy