Fight against rust

What is rust? Rust is one of the most common diseases in vegetable gardens. Trees, shrubs, wild herbaceous plants, and cultivated plants can all be affected. The fungi responsible for rust are numerous and belong to different genera (Puccina, Phragmidium, etc.). Symptoms of this disease are found on the aerial parts or stems and, much more rarely, on flowers and fruits. Rust can (but always) weaken the vitality of the plant or even cause its disappearance if the attack is severe. Some rusts have very complex cycles that involve one or two host plants and up to five different types of spores! The color of the spores varies depending on the type of rust and the type of spore it produces. Pustules are observed on the underside of the leaves and produce enormous quantities of microscopic spores carried by the wind. They can be orange, yellow, brown, black, white, or rusty, hence the name of the disease. There are also spots on the upper and lower surfaces of the foliage. Severely affected leaves turn yellow, wilt, and fall prematurely. Under what conditions does rust develop? The appearance of rust is favored by prolonged foliage moisture and particularly rainy conditions. It is present all year round in different forms. Which plants are mainly affected by rust? Rust affects flowers (carnations, roses, chrysanthemums, fuchsias, etc.), fruit trees and shrubs (pear trees, peach trees, gooseberries, etc.), trees (poplars, mahonia, etc.) and does not spare vegetable garden plants, leeks, beans, mint, etc.). Juniper is a host plant for rust; do not place them next to the vegetable garden or other crops susceptible to rust. How to fight rust? Space plants to promote air circulation and faster drying of the foliage. Remove affected parts! The fight against rust can be slowed by removing affected leaves as soon as they are seen in the garden, while they are still few in number. Stimulate your plants! Add manures of nettle, comfrey, horsetail, ferns, and garlic to encourage vigorous and healthy growth of plants and stimulate their natural defenses. Any diseased or dead plant material should be removed from the vegetable garden at the end of the growing season and burned. Do not compost contaminated plant waste; rust spores are extremely resistant and survive all winter! No specific rust fungicide is yet available. Some spray copper-based products.