I keep planting healthy azaleas, but over time the leaves turn yellowish and the bushes look unhappy. Why does this keep happening?
A. Sounds like chlorosis, a disease not caused by any bug or fungus. This is an iron deficiency in your plant, the plant version of human anemia. The most common cause of iron chlorosis in azaleas is a soil that’s too alkaline. Even if you’ve been using iron- rich fertilizer, the iron is unavailable to the plant if the soil pH is too high. This problem shows up most commonly with relatively new plantings, by the way. Big established azaleas that have survived the first few years can actually influence soil conditions favorably for themselves. Overly wet soil can also be a cause of chlorosis in azaleas, which have shallow root systems that rot easily in heavy clay soils with inadequate drainage. Middle Tennessee has a wide variety of soils, but clay soils that are relatively alkaline are quite common, thanks to the limestone bedrock not far below us.
Related Questions
- My azaleas have tiny black spots on the bottom of the leaves and the tops of the leaves appear yellowish white. What is causing this problem?
- My azaleas look washed-out, and there is black stuff under the leaves. Whats going on?
- What is causing the leaves of my azaleas to look stippled and bleached-out?