Azaleas, Camellias and Rhododendron are easy to grow when planted in the right USDA Zone, the right exposure to sunlight, the right soil, and proper fertilization. Though some varieties will tolerate full sun, for peak performance, most prefer afternoon shade, particularly in the hotter regions of the South. Moist, but well-drained soil is a must. Azaleas, camellias and rhododendrons will not tolerate wet feet. Humus-rich, fertile soil is preferred.
Using Amendment At Planting Time
When planting azaleas, camellias and rhododendrons, at time of planting, make sure to mix an organic soil amendment, such as mushroom compost, composted manure, or your own homemade compost at a 50/50 ratio with the soil removed from the planting hole. This will help to get your plants off to a good start by stimulating root growth. Newly planted azaleas can also be watered with a solution of Root Stimulator.
When to Fertilize
During the first spring, fertilize your azaleas, camellias, and rhododendrons just as the buds start to pop some color. Fertilize again, if needed, lightly in late summer but no later than 2 months prior to the first frost in your area. Late feeding could encourage new growth that might be damaged by a freeze.
Note: Because Encore Azaleas produce new flower buds every time new growth is produced, feed them right after each bloom cycle to encourage new growth and more flowers!
What to Fertilize With
Azaleas prefer an acid soil so fertilize them with an Azalea, Camellia & Rhododendron fertilizer or other types or ornamental plant foods that contain sulfur an/or iron. Avoid using fertilizers that contain too much more than 10 to 12% nitrogen (the first number in fertilizer) and more than 20% phosphorous (the middle number). Always refer to product label for application instructions.
Note: If the leaves on your azalea, camellia or rhododendron turn pale green or yellowish this could be an indicator of iron deficiency or soil that is too alkaline. Azaleas, camellias and rhododendrons prefer an acid soil with a pH ranging between 5.0 to 6.5 on the pH scale. Most nursery and garden centers sell soil testing kits or you can buy a soil testing kit online here. Your local extension service may also provide soil testing services.
Yellowing or fading of leaves can also be an indicator of insect infestation from chlorophyll-sucking insects or from soil that is constantly wet or soggy. Azaleas, camellias and rhododendrons do not like wet feet! If the soil is wet, to ensure good drainage, you might need to lift the plants so that they are planted and growing in a mound. When foliage is doscoloed, also check the undersides of leaves for the presence of lace bugs, aphids or other insects. If you find damaging insects use an insecticide labelled for use on these plants to control them. If you are unsure as to what is causing the yellowing of leaves snip off a branch with some leaves attached and take it to your independent local nursery and garden center. An experienced professional there should be able to diagnose the problem and offer a remedy.
Newly planted and young azaleas, camellia and rhododendron (3 years or younger) will require closer attention to soil moisture. In the absence of regular rainfall provide supplemental water as necessary to keep the soil moist, but not wet. Constantly soggy soil is a killer. During periods of dry weather, keep an eye on the foliage of azaleas. The outermost leaves will start to wilt when the soil necomes too dry. When providing water, rather than just splash a little water around plants more frequently, deep soak the soil.
Mature, well-established azaleas are usually quite drought tolerant. That being said, in the event of prolonged drought even large azaleas will appreciate a good deep soaking.