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How Do I Treat Powdery Mildew?

By Donna Emery ; Updated September 21, 2017

Powdery mildew is a fungus that causes a substance to form on the leaf of a flower. Treat powdery mildew with help from a certified horticulturist in this free video clip.


Hi, this is Donna Emery from Glover Nursery in West Jordan, Utah. How to treat powdery mildew in your garden. Powdery mildew is a fungus that causes just what it says, a powdery like substance to form on a leaf or a flower. It can be very disfiguring to a plant and it can also kill it if it's serious enough. There are biological and organic ways to treat powdery mildew and there are also chemical ways. But start first with good garden hygiene. Keep your plants cleaned up. Keep the debris away from them, give them lots of air space, lots of room . for the air to circulate and the leaves to dry off. Water in the early morning or the late evening when the sun is not shining directly on the plant but the best time is early morning because then they get a chance to dry out before night falls and they won't develop as much fungus. For organic controls you can use something like this which is a hydrogen peroxide based fungicide or this one which is actually based on a bacteria. This bacteria eats fungus so it will work on powdery mildew and many many other kinds of fungal infections as well. If you want to use a chemical, you can use something this Systemic or this all purpose broad spectrum fungicide but be very very careful if you are treating fruits and vegetables. Check the label to make sure that it is acceptable for vegetables. This one is, this one isn't so always always read the label. This is Donna Emery from Glover Nursery.


About the Author

Donna Emery has been a certified horticulturist for 20 years, has a two year degree in landscape design, and is a Utah-certified nursery professional.