One of my phlox plants, growing in potting soil in a large pot, each year loses its lower leaves. The leaves turn yellow and fall off. A plant pathologist could not identify any insect or mildew affecting the plant. I have tried to limit watering, sprayed with insecticde/fungicide, and divided the plant. The plant has been growing in partial shade but now moved now to full sun. The plant has been blooming but on largely leafless stems. Any thoughts?
One of my phlox plants, growing in potting soil in a large pot, each year loses its lower leaves. The leaves turn yellow and fall off. A plant pathologist could not identify any insect or mildew affecting the plant. I have tried to limit watering, sprayed with insecticde/fungicide, and divided the plant. The plant has been growing in partial shade but now moved now to full sun. The plant has been blooming but on largely leafless stems. Any thoughts?