Most home gardeners prize azaleas for their wide range of colors and low maintenance. By learning to prune these shrubs properly, you will be rewarded with healthy plants that bring spring color to your garden year after year.
When learning to prune azaleas, you must first know what type you have in your garden. The two types, evergreen and deciduous, have distinctly different growth habits. Evergreen azaleas, typically native to Asia, are the most common in local landscapes. They are more compact and dense, generally not as tall as deciduous azaleas, but they do have more vigorous new growth. Deciduous azaleas, mostly native to the Southeastern United States, are usually more open; often there is up to a foot between branches. Although these azaleas will lose their leaves in fall, some will take on a nice foliage color before dropping.
Why prune
There are many reasons, most commonly to maintain a desired size and shape. Pruning immediately after bloom lets gardeners maintain the size of the shrub, improve air circulation within the plant and remove any dead or diseased branches without affecting the next year’s bloom.
When to prune
Prune azaleas in the six weeks after their blooms fade. Deciduous azaleas typically do not need much pruning, but this is a good time to remove any dead, diseased or damaged branches, or particularly long shoots. The best way to keep a deciduous azalea from getting too leggy is to plant it in a location that receives ample sunlight. Whether you have deciduous or evergreen azaleas, avoid pruning after the end of June to keep from removing the next spring’s flower buds.
How to prune
Start with sharp, clean pruners, loppers or a hand saw and remove any dead or dying branches. Next, snip back leggy stems that are growing outside your desired shape. Azaleas are not meant to be severely hedged or turned into topiaries; they don’t do well when heavily pruned into tight shapes. Pruning by hand allows for a more natural look.
Pruning cuts can be made at branch unions (“thinning”) or at midstem (“heading”). Heading is more commonly used and will get the stems to a uniform length. Thinning completely removes a stem or branch back to another branch, bud or main trunk. This will result in a more natural growth habit that will require less trimming of long shoots.
Sometimes a more extensive process, rejuvenation pruning, is necessary if the azalea has lost vigor or has grown too large for its location. With this type of pruning, the azalea is cut back with a hand saw to near ground level, about 12 to 18 inches. As with traditional pruning, this should be done as soon as possible after blooming. By midsummer, adventitious buds will appear and send out new growth, and by next year you will not know the azalea had ever been pruned. This process may be scary, but reviving an old shrub can be quite satisfying, and it will extend the life of the plant and your landscape.
Wild Green Yonder is a monthly feature from the staff of Norfolk Botanical Garden, where Bailey Bunn is a horticulturist. Send gardening questions to [email protected].
