Azaleas are quite versatile and can be used a number of ways in the garden. They’re as effective in the formal foundation planting as they are in the natural shrub border. Though the most common azaleas are evergreen there are deciduous varieties as well. Deciduous azaleas are known as Mollis or Exbury Azaleas and are great in a woodland setting. They bloom in the early spring with vivid orange and yellow colors. Evergreen varieties of azalea bloom later in the spring with colors ranging from white to pink to purple to red.
When choosing any plant be sure that it is hardy for your area will up and die as soon as extreme cold weather hits.
Choose a site for your azalea which receives part shade during the entire year. Beneath the canopy of tall oaks and pines is usually ideal since azaleas prefer rich organic and slightly acidic soil. Grown in the dapple shade beneath the canopy azaleas will have longer periods of bloom than those planted in full sun. Azaleas planted in full shade will generally grow to be a weak plant overall with sparse blooms. Planting around shallow rooted large trees, such as maple, will result in competition for water and nutrients.
Planting azaleas should be done in either spring or fall. Spring, however, will allow you to see the plant in bloom. Azaleas, because of their small size, are usually sold in containers and will often become root bound. If you find this to be the case with your azalea simply make 3 or 4 cuts into the root ball to loosen the root system. This will give the plant’s roots the ability to grow freely. When sold balled and burlapped, remove the twine and pull the burlap away from the trunk of the plant. If the burlap is real there’s no need to remove it completely as it will decompose. Removing it can also cause the soil to fall from the root system.
Once the soil is properly conditioned and you’re ready to plant dig a hole at least twice, but preferably 3 to 5 times, the diameter of the root ball and just as deep. Digging any deeper and setting the shrub on disturbed soil can result settling. The wider the hole the easier it will be for new roots to grow and spread.
Next, place the plant in the hole making sure that the top of the root ball meets the existing grade of the garden. Never plant new or transplanted shrubs too low in the ground as it’s a major cause of premature plant decline. Backfill around the rootball with a mix of existing soil, peat moss and compost. Be sure to break apart any clumps of soil since they can cause troublesome air pockets beneath the surface. At about halfway, tamp the soil down lightly, water and let the soil settle. Finish backfilling, construct a saucer around the trunk of the tree and water again.
Azaleas in the Spring
Treat azaleas as you would rhododendrons. Each spring remove dead wood or any branches which were damaged over the previous winter. Wait until after they have flowered to prune for aesthetic reasons. These plants start setting next year’s flower buds over the summer, and late pruning will cost you some blooms next year, so get them pruned as soon as they finish blooming. Deadheading azaleas is tedious but important. This is the process of removing spent blooms. Removing them prevents the azalea from putting all its energy toward forming seed heads. Rather, the energy put forth will go toward the formation next year’s buds. When deadheading, be careful to remove only the spent flowers and not the forming bud.
Azaleas for zone 5: Hino Crimson (red), Stewartstonia (red), Herbert (lavender), Cascade (white), Delaware Valley (white), and Rosebud (pink).