Phlox Leaves Have Turned Yellow And Brown And Dry Up

Question From: Frankfort, Illinois, United States
Q: My bottom leaves on my tall phlox are turning yellow and brown. Some of the deformities are reaching the upper leaves. Many of the leaves on the bottom have turn brown and dried up. I looked for aphids and found note. I looked for spider mites and webs and found none. We had a wet spring, but it has been dry for weeks now and the deformities are progressing. Any ideas? Thank you for your help.
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A: Fungal diseases on the lower leaves of phlox are endemic. To prevent the spread the infected leaves should be removed. Bag them and put them in the trash. Then spray the plants, including the undersides of the leaves with a fungicide. Be sure to remove and destroy all the surface plant material after frost and treat the phlox every 7 to 10 days next spring. Best And Happy Yardening, Nancy