Growing Azaleas: Sun vs. Shade


Azaleas are absolutely magnificent when in bloom. Should they be planted in the sun or shade?
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We’ve all heard the adage: “Right plant, right place.” Knowing where to place your plants so that they receive the proper amount of sunlight will go a long way toward assisting your plants in reaching their full, beautiful potential.

Azaleas prefer dappled or filtered light, which can be found under an open canopy of trees. This is similar to their natural woodland habitat, where trees move in the wind and create variable shade and sun patterns. If azaleas are over-sunned in a home garden, the leaves will burn.

Because not everyone lives in a forest, how do you know where to plant azaleas? To find the right balance, first examine the amount of sunlight that hits your property. You should observe light patterns throughout the year. Here’s a quick guide to determining whether your garden location gets full sun, full shade, or something in between.

Types of Sunlight

Full (or direct) sun is an area that receives six or more hours of direct, unfiltered light per day. This is far too bright for most azalea varieties.

Part (or partial) sun is an area that receives less than 6 hours of direct light per day but more than 4 hours. Many full-sun plants that can tolerate a few hours of shade, usually in the morning, will thrive in this location. Azaleas may be too hot in this location.

Part (or partial) shade is a location that receives less than 6 hours of sunlight but more than 4 hours of sunlight, but it receives the majority of its light in the morning, when the light and heat are less intense. This type of light can be found on the east side of your house. Azaleas thrive in this location.

Light (or dappled) shade is considered any area that receives less than 4 hours of sunlight. This location receives filtered light through a leafy canopy. This is the ideal location for your azaleas.

Full (or heavy) shade is what you’d find under evergreens or in the day-long shadow of a building. Azaleas cannot grow in this shade because it is too dark.

If you don’t have a woodland, plant your azalea in a location that receives dappled shade most of the day or that is sunny in the morning and shady in the afternoon.

Sunlight peeking through the forest trees

What Happens if Azaleas Get Too Much Light?

Drought, sunscald, and insect and disease problems can all occur when azaleas are grown in too bright a location. Evergreen varieties can also burn in the winter.

Sunscald causes the leaves of a shrub to turn yellow and scorched. The edges and tips of the leaves turn brown.

Curled leaves are a sign of water stress, which is also a sign of overexposure to sunlight. 

Examine the inner foliage if you’re unsure what’s causing the yellowing leaves. If your shrub is healthy and deep green on the inside but yellow on the outside, it is receiving too much light.

Azalea leaves turning into autumn leaves
Half dried leaves under the heat of the sun

Azaleas grown in full sun will remain smaller and more compact. They bloom profusely, but the blooms fade quickly. They only bloom for a short period of time.

withered azalea due to drought

Soils dry faster under these conditions and root systems can dry out. You may discover that you need to water more frequently. When the soil is constantly wet and the sun heats it, the warm, moist soil conditions invite root rot. Insects may be drawn to your stressed, scorched shrub.

What Happens if Azaleas Does Not Get Enough Light?

Azaleas grown in full or heavy shade may not flower at all. There will be fewer blossoms if they do flower. The flowers, on the other hand, will last longer. Azaleas grown in full or heavy shade may not flower at all. There will be fewer blossoms if they do flower. The flowers, on the other hand, will last longer. 

A blooming purple azalea under the sun

As the stems stretch to reach towards light, the shrub’s habit becomes open and elongated. This is sometimes desirable because the shrub can develop a very elegant shape, but it also causes the shrub to grow scrawny and leggy.

Pink azaleas growing among oak trees

Azaleas grown in too much shade can weaken, making them more vulnerable to insect and disease problems.

Consider Your Climate

Azaleas prefer a little more shade in hot southern climates. They can tolerate more sun in cooler northern climates. Consider the amount of cloud cover in your area as well. You can grow these shrubs in a more open area if you have a lot of cloudy days. 

Also, consider how much winter sun your azaleas, especially the evergreens, get. The winter sunlight can be harmful.

Azalea Varieties That Can Take More Sunlight

In general, deciduous azaleas can tolerate more sunlight than evergreen varieties can. Several varieties tolerate brighter light. Here are a few to consider:

  • Piedmont Azaleas are deciduous trees native to the southeastern United States. They grow 5 to 10 feet tall and are hardy in zones 6 to 9. They have a suckering behavior and can form large colonies. Pink flowers bloom before the leaves.
  • Southern Indica or Indian varieties are hardy in zones 7 to 10. They grow to be 8 to 10 feet tall and wide, with bright purple flowers.
Beautiful and healthy pink azaleas
  • Encore Azaleas® are evergreen reblooming hybrids hardy in zones 6–10. There are numerous varieties that range in size from 2 to 5 feet tall and come in various flower colors.
  • Perfecto Mundo® series are evergreen, doubled-flowered rebloomers from Proven Winners. They are hardy in zones 6 to 9 and grow to be about 3 feet tall and wide. They can bloom pink, red, white, purple, and orange flowers.
  • Aromi hybrids are evergreen and hardy in zones 6 to 9. They can grow to be 4 to 5 feet tall and wide. They can bloom white, yellow, orange, pink, and red flowers. 

Azalea Varieties That Do Well in Shade  

While no azalea will thrive in complete shade, some varieties will thrive in partial shade. Most evergreen varieties and those that bloom in late spring or early summer can tolerate more shade. Look for the following:

  • Belgian Indica cultivars are evergreen, reach 3 to 4 feet in height, and are hardy in zones 9 to 11. Flower colors include pink, purple, red, white, peach, and orange.
  • Kurume Azaleas are evergreen shrubs that grow 2 to 4 feet tall and 3 to 5 feet wide and are hardy in zones 6 to 9. Flowers are pink, red, or lavender.
  • Rutherfordiana hybrids are hardy in zones 9 to 11, grow 3 to 5 feet tall and 4 to 6 feet wide, and are evergreen. Flower colors are white, shades of pink, reds, pale purple, and salmon.
  • Flame Azaleas are deciduous natives of North America that are hardy in zones 5 to 8. Their mature size ranges from 1 to 60 12 feet tall and 4 to 8 feet wide. Flowers are yellow or orange.
yellow azaleas plant growing in the forest
  • Maid in the Shade is a cross-genre collection. These trees are deciduous and hardy in zones 4–6. They can grow up to 8 feet tall and have pink, lavender, and yellow flowers.

What to Do if Your Azalea is in the Wrong Spot

If you’ve determined that your azalea is getting too much or too little sun, there are some things you can do to make the growing conditions more tolerable.

Pruning can help open up the tree canopy if your shrub is in too much shade. If your shrub is getting too much sunlight, you can create a protective screen with other shrubs and trees. However, it may take some time for them to settle into their new position. In either case, you can relocate your azalea to a more suitable location.

Transplanting Azaleas

Azaleas have shallow roots, so transplanting them does not require much digging. If your shrub is large, you may want to enlist the assistance of a friend; it will be difficult to move.

Plant in the late fall or early spring. Choose a day that is cool and cloudy with no wind. Water your shrub for a few days before moving it. You want it to arrive at its new home hydrated.

Create a new hole about 12 inches deep and as wide as the shrub. Begin digging the soil as far out as the branches can reach (the drip line) and proceed slowly and gently. You don’t want to cause any damage to the roots.

Transfer the shrub to the new hole and plant it. Plant it about an inch above the soil surface, with the crown of the plant (where the stems meet the roots) about an inch above the soil surface. Mulch and water thoroughly.

During the first year, keep an eye on your shrub’s water requirements. Don’t fertilize, but keep that layer of organic mulch in place. You won’t see much top growth at first as it establishes new roots, but over time, you’ll notice your azalea is much happier in its new home.

Beautiful and healthy azaleas in the front of the house
Alaine Connolly
Alaine has been working way too hard in horticulture since 1992, beautifying golf courses, resorts, and hotels. She is a part time landscape designer who works full time caring for a 28,000 square foot public garden. At home, she maintains her own 400 square feet plot. Alaine lives in northern Illinois - zone 5b.
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