The best and worst thing about azaleas is their rapid growth. While they fill in fast, producing masses of blooms, they also can grow into unsightly shapes in a single season if not given regular care. Older azaleas are especially prone to becoming unattractive with bare sections and long, random branches. There is no need to replace these older azaleas, however, since they can be rejuvenated quickly and without any damage to the plant.
Clean the pruning shears with bleach, either by wiping them down with a damp rag with a little bleach on it, or by spraying them with bleach that has been diluted with water. Cleaning the shears with bleach keeps disease from spreading between plants.
Prune the azalea after its flowering season. If your azalea flowers in spring and fall, wait until after the spring flowering. According to Cobb County Cooperative Extension of Georgia, cutting an azalea for rejuvenation should be done right after flowering so that new growth can mature and new buds can grow before the next flowering season.
Cut back the azalea's main branches at a point about six to 12 inches high, so that the remaining plant is 1 foot tall or less.
Remove any remaining smaller branches or sprouts.
Prune regularly stems, branches and sprouts that grow too long or out of balance with the plant, to keep the azalea's desired shape as it grows.
Remove any damaged or dead branches immediately to prevent disease and keep the plant healthy.