Tree & Flower Diseases

Keeping your trees and flowers free of disease begins with proper handling of the plant. Gardening shear blades, used for pruning, should be sanitized before using on each tree or flowering bush, to avoid spreading disease from one plant to another. A wound, caused by a careless gardening tool can be an entry wound for an infection. Some plant diseases affect both trees and flowers.


Canker is a plant disease often associated with rose bushes, yet it attacks other woody flowering plants and trees. The infection is caused by either a bacteria or fungus which typically enters the plant through a wound or fresh cut. Signs of canker are dead patches on the twigs, branches or trunk of the plant. Early signs might be a sunken area on the trunk. Sometimes the only indication a tree or flowering plant has the disease are raised bumps on the bark. Infected areas should be cut away from the plant and then the cut section treated with an antibiotic chemical. Between each cut, the gardening shears should be dipped in rubbing alcohol. Plants vulnerable to canker infection include those exposed to extreme temperatures, irregular watering, soil compaction, extensive defoliation, rough handling and sudden freezes and frost cracks.

Leaf Spot

Trees and flowering plants are susceptible to leave spot, a disease caused by fungus and bacteria. It is one of the most common tree diseases. Leaf spot typically strikes when the weather is moist and cool. As the name indicates, symptoms of the disease are spots on the leaves. On tree leaves they might have brown centers and black dots, while leaf spot in flowering plants might be yellow, red or brown. When the spots become more numerous, they merge with nearby spots forming large dead areas on the leaf. Leaf spot can be treated and rarely does permanent damage to the tree, yet can kill a flowering plant. To avoid leaf spot in flowering plants, avoid over watering and water in the morning, to allow the moisture to evaporate before nightfall. Chemical sprays can be obtained at the nursery to treat the infection.


Anthracnose is a fungus disease that affects some species of trees and flowers harder than others. For example, among trees, the sycamores are especially vulnerable. When it strikes a tree in early spring the tips of young twigs are killed, which is referred to as twig blight. As the disease progresses it then kills the buds, followed by leaves wilting on the season's new shoots. The leaves turn brown and drop during the final stage of anthracnose. Infected areas should be removed and the plant can be treated with a chemical, appropriate for the disease and plant type. Flowering plants vulnerable to the disease include the hollyhock, coral bells, peony, plantation lily, heartleaf bergania and violet.

Keywords: tree diseases, flower diseases, tree and flower diseases

About this Author

Ann Johnson was the editor of a community magazine in Southern California for more than 10 years and was an active real estate agent, specializing in commercial and residential properties. She has a Bachelors of Art degree in communications from California State University of Fullerton. Today she is a freelance writer and photographer, and part owner of an Arizona real estate company.