The azalea can be an evergreen or a deciduous shrub depending on the variety being grown. It is native to North America and regions in China. Azaleas belong to the same group of flowers as rhododendrons. They grow 2 to 15 feet high and 4 to 10 feet wide. The flowers of azaleas come in a wide variety of colors from white, orange, pink, red, burgundy and shades of purple. They are hardy in Zones 4 through 10 and bloom from spring into early summer.
How to Plant an Azalea
Turn over the soil in the area you want to plant your azalea to a depth of 5 to 6 inches. Azaleas love soil which is rich in organic matter. If the soil is sandy or clay-based, you will need to amend the soil. For clay soils, the University of Michigan suggests working into the soil a mixture of 50 percent ground pine bark, or rotted leaves, 25 percent sand and 25 percent soil. If the soil is sandy, work in a mixture of 50 percent soil and 50 percent organic material.
Dig a hole twice the width but no deeper than planting receptacle. Fill the hole halfway up with water and let drain. Remove the azalea from its pot by turning the pot upside down and striking the rim of the pot with a trowel until the pots slides off. Remove the azalea from the pot gently and hold it by the bottom of the rootball. If the roots appear bound, use a knife to sever and loosen the roots every 2 to 3 inches around the entire root ball, from top to bottom. Also, sever any matted roots from the bottom of the rootball.
Fill the hole halfway dirt. Place the azalea into the hole. The base of the stem should be 1 to 2 inches higher than the surrounding topsoil. Add or remove dirt so that the root-ball is sitting firmly on the soil. Adjust the azalea in the hole so it is sitting straight and level.
Fill up the hole with dirt, firming the soil around the azalea as you go. Water the azalea until it's well moistened. The Sunset Plant Finder recommends placing mulch around azaleas. Spread 2 to 4 inches of pine bark, straw, or any other organic mulch around the azalea to a diameter of approximately 12 to 16 inches. Keep the mulch at least 2 inches away from the stem.