By: Mary H. Dyer, Credentialed Garden Writer
Wild azalea (Rhododendron canescens) is a striking plant also known as mountain azalea, hoary azalea, or Florida Pinxter azalea. Although it is native to the southeastern United States, wild azalea grows in mild climates across much of the country. Want to learn about growing wild azaleas in your garden? Read on for more information.
Learn how to grow wild azaleas in the landscape is as easy as enjoying their blooms. Hummingbirds, bees and butterflies are attracted to the clusters of sweet-smelling pink or white flowers that appear before new growth in spring too. That being said, the plant is also attractive to wildlife, including hungry deer. Keep this under consideration before adding it to the garden.
Plant mountain azalea seeds in the garden in late fall, or propagate softwood cuttings in late spring. Allow spreading room of 36 to 60 inches (1-2 m.) between plants. Mature wild azalea shrubs reach mature heights of 6 to 15 feet (2-4 m.), with a spread of 6 to 10 feet (2-3 m.).
Mountain azalea thrives in full sun or partial shade, such as filtered light under tall deciduous trees. Too much shade will significantly decrease blooming.
Soil should be moist and well drained. Like all rhododendrons and azaleas, wild azaleas prefer acidic soil.
Water wild azalea regularly during the first two years. Water deeply at the base of the plant and avoid wetting the foliage. If you use sprinklers, irrigate in the morning so the leaves have time to dry before evening as damp leaves may invite fungal diseases.
Fertilize wild azalea in spring and again in late spring or early summer. Don’t feed after mid-summer, as the tender new growth is more susceptible to frost when temperatures drop in fall.
Spread 2 or 3 inches (6-8 cm.) of mulch around the plant to keep the soil cool and moist.
Pinch growing tips when new shoots are several inches long to promote healthy, bushy growth.
Mountain azalea rarely needs pruning. Prune in spring if you want to shape the plant or remove damaged growth, as wild azalea blooms on previous year’s growth.
Wild azalea is rarely bothered by pests but mites are sometimes a problem, especially in hot, dry weather. Insecticidal soap spray usually takes care of the problem.
Note: All parts of wild azalea plants are highly toxic and ingestion may lead to a number of severe symptoms, including stomach pain, nausea, vomiting, respiratory difficulties, weakness, loss of energy, depression, paralysis of legs and arms, coma, and death.
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|Sonia Uyterhoeven is Gardener for Public Education.|
Azaleas, as seen in the Garden‘s spectacular new Azalea Garden, provide home gardeners with wonderful spring color that extends from April into July (depending on the species). Evergreen azaleas provide year-round interest while deciduous azaleas often offer multi-seasonal appeal and lovely fall foliage. Azaleas are slow growing many of them, save some of the larger deciduous natives, make good candidates for foundation plantings. By following a few simple rules, it is easy to design effectively with azaleas.
Azaleas can be planted as specimens or in groups. The royal azalea (Rhododendron schlippenbachii) not only has luminescent pinkish-white flowers in late April/early May but also exquisite rounded foliage that is arranged like pinwheels on the stems, making it an ideal specimen plant.
The native flame azalea (Rhododendron calendulaceum) flowers in late May to early June in a variety of shades from fiery red-orange to yellow-orange (as the name would suggest). Specimens can reach up to 12 feet tall and 5 feet wide and rival any large Viburnum in the garden. When planted en masse, flame azaleas create a nuanced color harmony that will brighten any landscape they do not look congested or dense due to their graceful structure. Though deciduous, they can provide seasonal screening in your yard.
Pay attention to bloom time when planting azaleas in groups. Azaleas can generally be categorized by three bloom times: early, mid, or late season. I have visited gardens where azaleas are effectively planted so that they flower sequentially as one azalea fades its neighbor opens, providing color for extended periods. Or, weave a tapestry by planting groups of azaleas that flower at the same time.
When working with color in your garden, do not mix too many bright colors together. Azaleas come in a broad spectrum of color: white, salmon, mauve, pink, purple, and all variations of red, orange, and yellow. Blend bright colors with paler shades or white, so as not to overwhelm. Every design needs moments where the colors blend and the intensity subsides to give the eye a chance to rest and absorb the scene.
Pay attention to the size and the growth habit of your azaleas when combining in groups. Azaleas come in all shapes and sizes. Some have an upright habit while others have a more sprawling or creeping habit. Small azaleas are wonderful additions to a rock garden or a well-defined edge of a border or foundation.
Pair deciduous azaleas with other deciduous azaleas, and match evergreens with each other. Combining deciduous azaleas with evergreen azaleas in an overall planting is fine, but when placed side by side they generally look best with their own kind.
Place azaleas strategically in your yard where they can brighten up shadier areas. Years ago I worked at the New England Wild Flower Society’s garden, Garden in the Woods. The garden was ablaze in the spring with early ephemerals, native dogwoods (Cornus florida), redbuds (Cercis canadensis), and an array of flowering azaleas. Specimen azaleas were staggered through the landscape. A winding path wove through the garden enticing visitors to follow the color bursts and move through the landscape. Staggering the azaleas as focal points (rather than planting in large groups) gave the impression that the landscape flowed on endlessly the eye traveled from one colorful spot to another, making the space look more expansive.
Placing an azalea in a shady corner can brighten up or draw attention to an otherwise overlooked spot. Curves in garden beds can be accentuated in the spring with the bright burst of color. Evergreen azaleas add year-round structure to the garden, providing a solid framework when not in flower. Deciduous azaleas generally have a graceful habit and add a structural component throughout the season. They are also an important part in the fall garden design, highlighting areas late in the season and combining effortlessly with other plants that have fall color.
Interplant azaleas with a selection of native and non-native shrubs and perennials. Partner azaleas in the garden with woodland perennials such as ferns, wild ginger (Asarum), Solomon’s seal (Polygonatum), hosta (Hosta), toad lily (Tricyrtis), and many others.
Combine azaleas with other flowering shrubs. Extend the flowering season and experiment with texture and foliage by combining azaleas with other attractive shrubs. The oak-leaf hydrangea (Hydrangea quercifolia) makes a natural choice, thriving in part shade and providing interest with its broad, oak-leaf foliage and late season flowers. Large fothergilla (Fothergilla major) blends well with large native azaleas, while the dwarf fothergilla (Fothergilla gardenii) complements smaller cultivated varieties.
Underplant azaleas with spring bulbs. Make the most out of seasonal moments in your garden. Pair spring-blooming azaleas with daffodils (Narcissus) that flower at the same time yellow daffodils will enliven the scene, while white varieties with peach-colored corollas harmonize with many color schemes.
Carolina Native Nursery is in the business of growing native azaleas. In fact, you can find a flame azalea blossom in our logo. It’s been there since the beginning. Over the years we have grown them from seed (still do), searched in vain for other growers that could meet our quality and quantity needs, asked for help from countless sources, and continued to work hard to meet our client’s needs. As a result, we have certainly met a few obstacles along the way but have rededicated ourselves to produce the quality and numbers necessary to meet our client’s needs. Carolina Native will be providing up to date information on the deciduous azaleas we offer for sale, our methods and time frames in growing them from seed, selections of plants identified and produced from others, and as much information as we can.
We think there should be native azaleas in everyone’s garden. As far as we are concerned, these plants are truly the gems of our indigenous landscape. Plus, we know they have been ‘transplanted’ from many roadsides, woods, and forests into people’s gardens as long as people owned shovels. Please leave these plants in the wild. If you are a native azalea enthusiast we have the plants for you.
Our staff collects seed and need more from as many sources as possible, please reach out to us. You can send us some seed too. If you own nursery that is looking for native azalea liners, give us a call or send us an email. We want to supply you with some liners. For wholesale clients, we ship plants everywhere from Atlanta to Maine, out to Lake Tahoe, even a box full to Shanghai for trials. Let us know what and where your needs are and we will try to help.
We hope to hear from you as we build our information. Editorial comments are more than welcome. Our vision is to create the go to resource for everyone interested in native azaleas. The staff at Carolina Native Nursery knows there are many folks that want to know more. We look forward to raising awareness, providing the plants, and helping get these plants in gardens, landscapes, and back in nature everywhere they have traditionally been found.
14000 seed-grown native azalea liners in their first year. These will all moved up into 1-gallon pots the next spring.
1-gallon native azaleas in their 2nd year. All of these will be moved into 3-gallon pots the next spring to finish and ready for sale.
3 gallon Sweet Azaleas, Rhododendron arrborescens. These are rooted in and ready to go.
Nationally known native azalea authority Ernest Koone III still remembers one of the first things he ever read about these spring- and summer-flowering plants. It was the first sentence in a small, undated booklet, and he was just 11 or 12.
"The native azalea species of the Southeastern United States have been called, by many plant authorities, the most beautiful of all our indigenous shrubs."
The booklet was written by Fred Galle, longtime director of horticulture at Callaway Gardens in Pine Mountain, Ga., where the Plumleaf azalea, Rhododendron prunifolium, is the signature plant.
The statement “has become a part of me,” says Koone, president of Pine Mountain’s Lazy K nursery, the largest producer of native azalea species and cultivated varieties in the country. “Absolutely no other native American plant group compares with the native azaleas in variety and brilliance of color and fragrance, on shrubs large and small with bloom-times from early spring to late summer.
Here are tips from Koone about how to grow azaleas, the most native of American plants.
Most of the 17 species of native azaleas occur from Texas to Florida and along the Eastern Seaboard from the coast into the Appalachian Mountains up to Virginia. The natural range continues north up the Atlantic coast into Maine and Canada. A single western species found in California, Washington and Oregon, R. occidentale, is very difficult to grow east of the Mississippi. One species, R. canadense, grows from New Jersey northward into Canada.
Many native azaleas — R. prunifolium (plumleaf azalea), R. atlanticum (coastal azalea) and R. vaseyi (pinkshell azalea) — are very cold hardy and can grow far outside of their natural Southern range. Others, such as R. canadense, which grows from north of New Jersey to Labrador, won’t grow well south of New Jersey. High elevation Southeast plants, such as R. prinophyllum (roseshell azalea), won’t do well in lower elevations, even in the Southeast. In these cases, summers are too hot. Conversely, some southernmost species — R. austrinum (Florida flame azalea), R. canescens (piedmont azalea) and R. alabamense (Alabama azalea) — will grow in northern climates but they often won’t flower there because the buds, which form in the summer, will freeze before they can open in the spring. Exceptions can be obtained and plants can bloom a considerable distance from their native range by siting them in appropriate micro-climates.
The most common mistake in planting native azaleas is thinking that these are shade plants and underestimating how much sun they need to bloom well. Early bloomers (March-May) and middle season bloomers (May-June) do best with at least a half day of sun. Late bloomers (July-August) need afternoon shade because of the intensity of the summer sun.
How to plant
Native azaleas need a well-drained, acidic, humus-rich garden soil. To achieve this, amend the soil with organic matter such as ground pine bark, fine pine bark or a bark-based soil additive. A soil pH of 5.0-6.0 is ideal. Because azaleas are shallow-rooted, plant the root ball slightly above the soil surface. Mulch lightly, preferably with pine straw.
Keeping young plants well-watered for the first two years while they establish root systems is critical. A rule of thumb: Keep the soil gently moist. Azaleas cannot tolerate standing water.
A high-nitrogen fertilizer, such as 12-6-6, is recommended. Plants should be fertilized in spring when new leaves emerge and again just before July 4. Don’t fertilize after Independence Day because that will stimulate additional new growth late in the season that could get killed by frost.
Many native azaleas can grow into small trees 12 feet tall or higher. With judicious pruning, they can be formed into bushy shrubs and kept six feet tall or less. Flower buds form in June for the next year's bloom — so prune early and mid-season bloomers immediately after the flowers fade. Prune late-season bloomers any time.
There are three common mistakes in planting native azaleas. They are:
Why pick natives?
Native azaleas are different in several key ways from the azaleas seen most often in garden centers. Non-native azaleas sold in nurseries are bred with plants from Asia. These are small-to-large, evergreen shrubs, whereas native azaleas are deciduous and can grow into small trees. Many native azaleas are distinctly fragrant, whereas the Asian plants have almost no fragrance. Native azaleas have a greater range of colors than the evergreens — there are no yellow or gold shades in the evergreens.
Know more about how to grow azaleas? Leave us a note in the comments below.