Azaleas usually won't flower well if planted under trees with dense foliage, such as maples, beeches, and pines. Plant in the diffused light under widely spaced, high-crowned trees like oaks and tulip poplars. Deer and rabbits may eat many of the flower buds as they browse in the winter, particularly if the weather is harsh and other food is scarce. Flower buds can also be damaged by cold, dry winds, particularly when warm winter weather is followed by a period of bitter cold. My azaleas always turn yellow or purple in winter.
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Like all evergreen plants, azaleas periodically lose some of their foliage, and the leaves may turn yellow, red, or purple before they fall. Often the only leaves that remain are those that surround the flower buds at the tips of the branches. This characteristic is linked to the genetics of the parents used to breed garden azaleas. The degree of leaf coloration or loss is a function of parentage and not the severity of the winter. In unusually cold winters, certain azaleas may lose more leaves than they would in mild winters.