Leaf Spot Disease
Leaf spot disease, caused by the fungus Entomosporium maculatum, is a common issue faced by Photinia Red Robin growers, particularly in moist climates. This fungal disease presents itself as small, circular, red spots on both the upper and lower surfaces of new leaves, which can eventually merge to form larger, maroon blotches on heavily diseased leaves. Mature leaves usually develop spots. These spots are dark brown or gray in color. They are surrounded by reddish-purple rings.
To treat leaf spot disease in Photinia Red Robin, it is crucial to act promptly. If the plant is only partially affected, remove the damaged leaves and burn them to prevent the spread of fungal spores. Additionally, prune back hard in mid-May, which provides the plant with sufficient time to recover with the onset of summer.
It is also advisable to plant healthy plants in an isolated location, away from other plants with red tips, to prevent the spread of the disease.
Rust and leaf spot are two fungal diseases that affect privets. Both cause spots or discolouration on the leaves of the plants, but can be distinguished by their colour — rust is reddish-orange in appearance, while leaf spots are usually yellow or brown.
If caught early, these problems can often be resolved with fungicides. However, it is important to thoroughly cover all affected areas in order to prevent further infections.