What causes black spot on holly bush leaves (male & female?
Answer Sounds like tar spot fungus. Tar spot – Tar, or black, spot causes considerable damage to hollies, especially in the Southern States. A fungus, Phacidium curtisii, attacks the plants during prolonged wet weather. Leaves and berries turn black. This disease is seen more often after a rainy spring. We cant control the weather but we can avoid adding to the problem. Avoid wet foliage by watering early in the day and try using a soaker hose or watering wand to apply water directly to the soil. Prune out old and crossing branches on dense shrubs. Thinning the plants increases air circulation and reduces the risk of disease. I would spray the foliage with a fungicide. Fungicide that are registered for tar spot are: Banner, Maxx, Mancozeb, Daconil 2787, and Dithane. These are usually applied in the spring on new leaves. Check with your local garden/nursery type store for a fungicide for tar spot.
