I have rooted many azaleas. Some of my mother plants are almost 40 years old and were rooted from plants my mom had. We found the best way for us was to choose a branch at the bottom that is flexible. About halfway up the branch scratch the bark off and weigh it down on the soil with a brick or some other heavy object. After 2-3 months lift the brick and carefully try to lift the branch. Just barely give it a tug because you don't want to pull it up. We leave ours like that for almost a year. Use your judgment to decide if it has grown adequate roots. When you think it has lots of good roots cut the branch where it grows out of the mother plant. At that point i put the rooted cutting in a pot and grow it on until it has new growth. i found using this method gave me well rooted plants that did not fail when planted out.
