Answer: The only way to tell if they are dead or not is to start at the tips of the branches and cut off pieces little by little. If there is no green layer anywhere inside, (look very carefully), then that "wood" is dead. Work your way gradually down toward the base of the plant, neatly removing any dead wood. Since what you are removing is already dead, you will not hurt the plant. If worse comes to worse, and you have removed all or most of the top, and you are the patient type of gardener, you can wait for a year and see if the remaining wood and roots can send up new growth. If so, you will probably have lovely azaleas. Sometimes these plants will leaf out again if treated well.
Azaleas need an evenly moist yet perfectly drained (not soggy) soil and are rooted close to the surface, so you really need to keep an eye on watering in order to establish new ones in your garden. They appreciate a light mulch and also need a loose soil high in organic matter. Finally, they require an acid soil. In my experience, they do best in partial shade, but they will also grow in more or less sun if cultural conditions are otherwise met.
Good luck with your azaleas!
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