Rust is a fungal disease that infects ornamental and edible plants in wet and humid conditions. It is caused by many different species of fungi. Some types of rust infect only one type of plant.
Rust is recognized by powdery, orange- to red-colored spores grouped in pustules on the underside of infected leaves and sometimes stems. Yellowish spots also appear on the upper sides of the leaves. Roses, Chrysanthemums, Beans and Snapdragons are a few of plants often infected with Rust.
- If available, plant resistant varieties. Contact your local cooperative extension service for more information.
- Avoid overhead watering, which helps spread the disease.
- Prune to keep plants open and increase air circulation. Remove infected leaves as soon as you see them.
- Practice good sanitation, disposing of prunings and fallen leaves in winter to prevent reinfection. Apply fresh mulch.