Since we continue to get these heavy rainfalls here in Central Florida, followed by hot humid weather, fungus continues to thrive. This week I’m going to talk about Powdery Mildew. I’ve been seeing it a little more often than I have in the past, mostly because of the weather conditions I just mentioned. It will also be more common in shady areas, since plants will not dry off as quickly. The Powdery Mildew pictured here is on a Crepe Myrtle.
Powdery Mildew looks a little different from plant to plant. But all variations will start with small white spots like pictures here. It will quickly spread throughout the leaf and cover the top of it. When it gets to this point it will look like someone sifted baby powder on this plant, hence the name of this disease. If left untreated it will cause stunted growth, and cause the leaves to turn yellow and the plant to defoliate.
You want to make sure that you treat shrubs for Powdery Mildew as soon as symptoms are visible, to prevent it from spreading. There are many different types of fungicide that will work on this disease. A foliar fungicide spray will clear it up easily. Even the use of Horticultural Oil would be beneficial. Heritage works well, but it a very expensive option. Any of your copper based fungicides would be a less expensive option for you. Multiple treatments may be needed depending on the product used. As always, THE LABEL IS THE LAW! Make sure any product you use, you read the label thoroughly. Make sure the plant and issue is listed on the label. Misuse of product is not only a waste, but against the law as well. I highly recommend contacting your local Lawn Care professional to help you with any issues you have. They will have the correct products and equipment to take care of this and any other issue you may have.