Powdery Mildew, Rust and Fungus
Powdery Mildew, Rust and Fungus usually appear when the summer heats up. Powdery mildew starts with a whitish cast on the surface of the leaf. It turns the leaf brown and the leaf dies. Rusts can appear on either the tops or the undersides of leaves and, as the name indicates, are brownish red in color. Other fungus manifest as gray or black discolorations on leaves, stem or branches. All are treatable. A 1% solution of sulfur and water, with a little dish soap mixed in, works well. Common hydrogen peroxide is also a potent fungicide, which can be used straight up or diluted with water up to 50%. Be sure to test a small portion on the plant first when using hydrogen peroxide mixtures and, as with all sprays, never spray a plant when it is sitting in direct sunlight. Controlling water application is critical when you have fungus problems. Never get the leaves wet. Always water at the base of the plant, preferably in the morning. Roses in particular suffer from a lot of fungus problems and may benefit from trimming out crowded growth in the interior of the plant to increase air circulation.
This entry was posted
on Tuesday, August 18th, 2009 at 9:57 am and is filed under Avant Gardening Series, Flowers, Gardening.
