Answer: The fungus that's attacking your plants overwinters on dead leaves and other plant remains, so be sure to clean the iris bed up and remove any plant debris. Spores are produce in spring and infect leaves, especially if the weather is warm and wet. Tohelp prevent infection, and the spread of infection, give your plants enough space between so the leaves are not touching one another. You can apply a garden fungicide such as lime-sulfur to the leaves if you notice spots beginning this spring. Don'tspray until the leaves are 6-8 inches high. You may have to spray every 10-14 days if the weather remains warm and wet.
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