Persimmon trees can reach heights of up to 25 feet tall. The most common cultivars have few disease problems, but can contract some illnesses that will hinder its growth. Knowledge of these diseases will help caregivers of this plant diagnose and solve the problem.
Crown gall consists of knots that form at the base of the plant where the roots join the stem. These galls are caused by the bacteria Agrobacterium tumefaciens, which lives in the soil and only enters plants by way of wounds. If the disease progresses too far the plant will turn yellow and become stunted and sickly. Once the tree infected, you cannot cure this disease. You must get rid of the plant and sterilize the soil to prevent spread. To prevent this disease, try to avoid accidentally wounding the tree.
Anthracnose causes leaf spots on persimmon. The fungi that causes it, Colletotrichum gloeosporioides, lands on the leaves as spores in the spring. Soon, depressed, dark lesions appear on the leaves, causing them to drop early. This infection will not kill the tree, but will cause premature defoliation which may be unsightly. Once this disease infects the tree it is difficult to get rid of it in one season. To help promote health, rake and dispose of all infected leaves and twigs during the growing season and in the fall. Prune the tree in winter to increase air circulation and remove infected branches. Fungicides are unreliable and only sometimes control the disease.
Premature fruit drop and blossom drop often occur on young trees. This can occur as a result of over-watering or over-fertilization, insufficient sunlight, excessive shoot growth or lack of pollination. Fruit drop is not usually a serious condition, but may cause a mess. To help prevent it, alter growing conditions to best suit the plant. Removing all but two fruits from each twig in May and June may help promote healthy growth as well.
Root rot occurs in persimmon residing in waterlogged soil. Armillaria fungi fester in this environment and eat at the roots. As this occurs, the top of the plant begins to yellow and wither, and in particularly bad cases the leaves may drop. Severely infected plants will not live, and you must remove the entire persimmon tree in order to stop the spread of the disease to other plants. To cure slightly affected plants, dig out the soil from around the roots and allow them to dry. Prune infected roots down to healthy tissue and replant the persimmon in a new area. Water sparsely.