Your Hosta are infected with Anthracnose. Anthracnose is a fungal disease commonly affecting Hosta, particularly during warm and humid conditions. The disease manifests as irregular brown or tan spots on the leaves, which may enlarge and cause portions of the foliage to die. To treat Anthracnose, begin by removing and destroying infected leaves to prevent the spread of the fungus. Improve air circulation around the Hosta by spacing plants appropriately and trimming surrounding vegetation. Avoid overhead watering and keep the leaves as dry as possible. Applying fungicide labeled for anthracnose on ornamental plants can help protect healthy foliage. Regular monitoring and maintenance will ensure your Hosta stay vibrant and thriving. More information on Hosta pests and diseases can be found in this article from Michigan State Extension Service. The article can be found here: Hosta Pests and Diseases - Gardening in Michigan

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