The best time to prune your Azalea plants is when they are actively growing. This is a period when they have finished their major flowering and are starting to put on new growth. The objective is to avoid pruning off any new flowers that are developing. That is why it is best to leave pruning until the end of a major flowering. Many people use hedge trimmers to prune Azaleas and this is okay. Generally it is best to prune the semi-hard wood if possible as pruning the hardwood can result in dead stems. If you have to prune the hardwood, water the plant well to reduce the effect of moisture loss from the stems. The plant will recover from pruning the hardwood, however it tends to take quite a while for the plant to recover and put on new foliage.
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