Azaleas Made Simple
Here's everything you need to know about growing the South's favorite shrub.
Azaleas prefer light shade and acid soil containing plenty of organic matter. This one is 'George Lindley Taber,' a Southern Indica Hybrid.
Azaleas are the one group of plants Southerners never tire of learning about. Here are answers to some basic questions readers ask about these popular shrubs.
Do azaleas need shade or sun?
Actually, they like a little of both but not too much of either. Plant them in blazing hot sun, and they may suffer leaf scorch or become targets for leaf-sucking pests such as spider mites and lace bugs. Plant them in dense shade, and they won't bloom. A good location is where they receive either dappled sun all day or sun in the morning and light shade in the afternoon.
What kind of soil do they like?
Azaleas do well in moist, acid (pH 5.5 or so), well-drained soil with lots of organic matter, such as peat, compost, chopped leaves, or ground bark. They won't grow in heavy clay, pure sand, or alkaline soil. If your existing soil is too bad to fix, plant azaleas in raised beds or containers.
How and when should I fertilize them?
Azaleas growing in acid, nutrient-rich soil don't need much fertilizer. But if your soil is so-so or you notice the leaves turning yellow between the veins, feed them with a slow-release, acid-forming azalea fertilizer that contains iron and sulfur, such as Holly-Tone 4-6-4 or Scotts Evergreen, Flowering Tree & Shrub Food 11-7-7. Apply right after plants finish blooming in spring and again in midsummer at the rate specified on the label. If your azaleas need an immediate pick-me-up, switch to Miracle-Gro Azalea, Camellia, Rhododendron Plant Food 30-10-10. Both roots and leaves quickly absorb this liquid fertilizer, but you'll have to apply it more often than the others.
How and when should I prune them?
Do so immediately after the plants stop flowering in spring. If you wait until summer, you'll remove most of next year's flowers. Use hand pruners, not hedge trimmers. Cut back to a branch or bud, and don't leave big stubs.
How big will azaleas get?
That depends on the type. Low, spreading Satsuki Hybrids, such as 'Gumpo,' grow only a few feet tall. The popular Kurume Hybrids, including 'Coral Bells' and 'Hershey's Red,' form dense shrubs 3 to 4 feet tall and wide. Southern Indica Hybrids, such as 'George Lindley Taber,' 'Formosa,' and 'Pride of Mobile,' can grow 8 feet tall and wide. Don't plant these big guys under low windows.
When is the best time to plant azaleas?
Spring and fall, when temperatures are cool, are excellent times. But if you buy in spring when the azaleas are blooming, you'll be assured of getting the colors you want. Summer planting is okay, but you'll have to water frequently during hot weather.
Can I plant one of every color together?
Hey, it's a free country, but we'd rather you didn't. You'll get a much better show by planting a mass of a single hue.