Answer: Azalea blooms generally last for only a few weeks, so that is normal. In order to make suggestions about the rest of your question, it would be helpful to know some of the symptoms. However, if they are turning a speckled white, they may be suffering from a lace bug infestation (these often become visible soon after bloom).
If they are turning brown, they may be suffering from over watering, under watering, too much sun or too much wind.
If they are turning yellow, they may be protesting your soil. Azaleas do not do well on clay because they require a humusy, organic soil that is moist yet well drained (not soggy). It must also be acid. They are shallow rooted and intolerant of digging and other forms of root disturbance, including changes in grade.
You might wish to contact your County Extension (560-4150) if you have doubts about your soil or for a more specific diagnosis and suggestions as to what to do for them now. Good luck with your azaleas!
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