With more than 10,000 varieties of azalea available, if you garden in USDA hardiness zones 7 or above, you will be able to add an azalea to your landscape. Azalea shrubs can be evergreen or deciduous and thrive in partial shade and acidic soil. Unlike many shrubs, azalea bushes generally grow in an attractive form naturally. Most cutting, or pruning, is done to maintain size, increase fullness and produce abundant flowers. Azalea flower buds are formed on old wood from the prior growing season, so cutting your azalea should be done shortly after it blooms, promoting growth to ensure blossoms next year.
Remove any dead or broken branches on your azalea using pruning shears or loppers. Cut the dead branch off close to the base of the shrub if the entire branch is dead, or an inch above where you see growth on the branch. A method to determine where a branch is still alive is to use your fingernail to carefully remove about 1/4 inch of bark from the branch. If the underlying layer is green, that part of the branch is viable and alive.
Take a look at your azalea shrub to determine exactly what you want to do and how you want the bush to look. Your azalea may have grown too tall and is blocking a window. Or, the shrub may need cutting to have a fuller, denser look. Examining the azalea before cutting will guide you to cut only the necessary branches to accomplish the look and shape needed.
Trim any long branches that have bolted beyond the basic shape of your azalea shrub. Ideally, an azalea shrub form should appear natural in a uniform, rounded shape. Occasionally, one or more branches grows several feet beyond the main bush, either upward or from the side. Follow the branch down into the shrub until you find a junction where other branches are growing. Using sharp pruning shears, cut the overgrown branch off at the junction.
Rejuvenate older, sparse-looking azalea shrubs by selecting three to five older, thicker branches and cutting them back to one-third their original length. This will force the branch to grow new healthy branches, making a fuller bush. After cutting back the thicker branches, trim back any smaller branches only to shape the azalea.