Answer: It sounds like your azaleas are suffering an iron shortage. The yellowing of the leaves is called chlorosis. It probably isn't happening to your other bushes because their iron demands are not as hefty as the azalea (happened with my azaleas last spring). I corrected the problem with a product called Ironite. The change was amazing. I could almost sit and watch the green of the leaves reappear. Iron deficiency can occur in soils with a high calcium content, soils that are poorly drained, soils with ahigh pH (which you also don't want because azaleas like low pH, acidic soils) and, as mentioned earlier, and iron is more readily available in acid soils. The product I mention above is widely available at retail outlets and garden centers. Apply perpackage instructions.
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