With hundreds of azalea varieties available in a range of hardiness levels, this showy shrub generally grows in zones 5 through 9, covering much of the continental United States. And, in the right conditions with just a little maintenance, they can live for up to 50 years!
How much do you know about azaleas? Here, we’ve got fun facts about azaleas, how to grow them, how to care for cut azaleas, and much more information about this member of the genus Rhododendron. Once you finish reading this article, you’ll be ready to head to the nearest nurseries that specialize in azaleas so you can pick some up and start planting azaleas today!
Azalea Fun Facts
Also known as the “Royalty of the Garden,” azaleas are toxic when eaten, so they may not be the best plant choice if you have pets who like to munch on greenery. Other azalea fun facts include:
- Azaleas can be either deciduous (losing their leaves every fall) or evergreen (staying mostly green throughout the year).
- Thanks to their toxicity, giving somebody azaleas in a black vase was once seen as a death threat.
- There are more than 10,000 different cultivars of azaleas.
- While azaleas are most commonly pink, they can also be white, red, purple, orange, or yellow.
- The United States, Korea, and Japan all hold festivals to celebrate azaleas.
- Most azalea cultivars only bloom once a year, in the late spring or early summer, but some, such as the Encore series, bloom twice a year – once in the spring and once in the fall.
What Are the Differences Between Azaleas and Rhododendrons?
If you have a difficult time telling azaleas and rhododendrons apart, you aren’t alone! In fact, azaleas and rhododendrons are both included in the rhododendron genus. Typically, azaleas have smaller leaves than rhododendrons spp. and funnel-shaped blooms with five stamens, while rhododendrons tend to have bell-shaped flowers with 10 or more stamens.
How to Care for Cut Azaleas
Want to create stunning flower arrangements using the azaleas you’ve grown? Follow these tips for storing bouquets and caring for your azaleas starting from the moment you cut them:
- Take a bucket filled with 1-6 inches of clean, acidified, warm water with you when you go to cut your azaleas. Cut the stems at an angle, remove any foliage that would fall below the water line, and immediately place the blooms in the water bucket to prevent air bubbles from forming in the stems – this helps improve their vase life.
- Harvest azaleas in the morning or evening when the flowers are cool. Cutting stems in the heat of the day can result in rapid wilting.
- After harvesting, place the bucket in a cool room in your home, away from direct sunlight, and let the flowers rest for a few hours before arranging them.
- Fill your vase and another bucket with room temperature water. Hold each flower under the water in the second bucket and recut the stems (again, at an angle) with clean, sharp shears, then place it immediately in the vase.
- After you’ve arranged the azaleas, keep the bouquet in a cool, shady place. Change the water in the vase every day. After a few days, repeat step 4 with a clean vase.
How to Grow Azaleas in Your Garden
While some people believe growing azaleas is difficult, they can actually be quite hardy when you give them the conditions they require.
Azalea Water, Soil, and Sunlight Needs
Prone to root rot and leaf fungi, azaleas do best with damp, well-drained soil that neither stays soggy nor gets too dry. Water the base of the plant rather than spraying or dripping water it on the leaves.
Acidic soil is best for azaleas. If you have neutral or alkaline soil, you can build raised beds 15 to 18 inches deep filled with a mixture of half coarse sphagnum peat moss and half finely milled bark. To keep the soil in the preferred soil pH range of 4.5 to 6.0, make a mixture of 1 part iron sulfate to 3 parts garden sulfur and apply one pound per 100 sq. ft. of garden bed.
Azaleas prefer dappled shade or partial sunlight, with morning sun or a canopy of shade trees being ideal.
Where to Plant Azaleas
Too much sun can burn or bleach azalea leaves, so you should try to plant them on the north or east sides of your house rather than the west or south sides.
When Should I Plant Azaleas?
Azaleas do best if you plant them in the late spring or early fall. Since these plants have shallow roots, you should dig a hole the same depth as the root ball and at least twice as wide so the azalea roots have plenty of room to spread out.
When Do Azaleas Bloom?
Azaleas typically bloom from late March to mid-May, depending on the cultivar and growing location. Some species also bloom again in the fall.
How to Maintain Azaleas
Azaleas need plenty of mulch: peat moss; pine needles; oak leaf mold; or aged pine, oak, or hemlock sawdust help keep the soil moist and acidic. Fertilizing azaleas isn’t really necessary as long as you maintain the mulch at a level of 2 inches deep and 2 inches away from the trunk, but you can add acidifying fertilizer in late winter or early spring if your soil is naturally alkaline or neutral.
Once the azaleas have been established, spring rain is typically enough to keep them hydrated. However, if it’s been especially dry, go ahead and water your azaleas in the morning so the sun can cause the moisture to evaporate from the leaves before it can cause fungal diseases.
You can prune azaleas (after they bloom and before the 4th of July) when they start looking a little ratty or overgrow the area where you want to keep them. Pruning azaleas also helps keep these shrubs tight, compact, and full of flowers.
Azalea Pests and Diseases
While azaleas tend to be low maintenance compared to other plants, they can still be affected by problems, like:
- Lace bugs
- Powdery mildew
- Azalea leafminers
- Petal blight
- Caterpillars
- Rust
- Stunt nematode
- Azalea gall
- Twig blight
Complementary Plants for Azaleas
The best complementary plants for azaleas are those with similar soil and sunlight needs (e.g. acidic soil and partial sun), such as:
- Mountain laurel
- Hydrangea
- Plantain lily
- Bleeding heart
- Holly
- Spotted dead nettle
- Summersweet
- Barberry
- Witch hazel
- Viburnum
How to Care for Azaleas in Containers
If you live in a climate with harsh winters (or simply don’t have access to a garden of your own), azaleas can do well in containers, especially if you like to keep your home on the cooler side – Azaleas as houseplants do best at temperatures around 60-65° F.
Keep your azalea in a location where it can either get bright indirect light all day or direct sunlight in the morning with afternoon shade. Also, be sure to keep your azalea away from heating vents. Azalea soil should be moist, but not waterlogged, so proper watering is paramount, and a humidifier is beneficial, too.
Interested in caring for other flowers? Check out our begonia care tips next!
Azalea Meaning and Symbolism
The word “azalea” is derived from the Greek word for “dry” and likely comes from the flower’s preference for well-draining soil. Interestingly, azaleas have many different meanings and symbolism, including:
- Family and familial duty
- Homesickness
- Wealth and abundance
- Elegance
- Fragile love
- Developing passion
- Feminine beauty
- Temperance
- Azalea meanings also vary depending on the color:
- Dark pink and red azaleas both symbolize love, passion, and romance
- White azaleas represent purity, restraint, and civility
- Yellow azaleas stand for happiness, friendship, and positive energy
- Purple azaleas symbolize royalty and nobility
Varieties of Azaleas
With more than 10,000 varieties of azaleas in many colors and hardiness levels, you’re certain to find one you absolutely adore. First, you need to know what USDA growing zone you live in: here is a USDA growing zone map. While the majority of azaleas thrive somewhere between zones 5 through 9, the University of Minnesota has created multiple varieties tolerant of colder climates, with some able to live in zones 4 or even 3.
‘Fireball’
As the name suggests, ‘Fireball’ azaleas bloom in fiery hues of bronze, red, and orange, providing a spectacular show when mass planted in shrubscapes, foundation plantings, and big beds.
USDA Growing Zones: 5–8
Height: 4–6 feet
Sun Exposure: Partial
‘Northern Hi-Lights’
Developed by the University of Minnesota, these blooms are cream to pale yellow with bright yellow highlights. ‘Northern Hi-Lights’ have some resistance to mildew and excellent cold tolerance – they’re hardy to zone 4 and may survive in some zone 3 gardens as long as you protect them from strong winds.
USDA Growing Zones: 4–7
Height: 4–5 feet
Sun Exposure: Partial
‘Duc De Rohan’
‘Duc De Rohan’ has an extended flowering time from early to late spring and features big, salmon-pink flowers. Since this cultivar grows more wide than tall, it’s ideal for the pruning and training required for bonsai cultivation. Note that if you want to keep this azalea as a bonsai, you will need to perform root trimming every 3-4 years to keep growth compact and restrained.
USDA Growing Zones: 8–9
Height: 2–3 feet
Sun Exposure: Partial
‘Lemon Lights’
‘Lemon Lights’ are showy azaleas developed by the University of Minnesota with blooms that are a lighter yellow on the edges, blending into a more golden tone near the throat. Cold-tolerant and exceptional at attracting pollinators, these azaleas need afternoon shade, especially in warmer climates.
USDA Growing Zones: 4–8
Height: 4–6 feet
Sun Exposure: Partial
Encore
The Encore series of azaleas contains more than 30 varieties, all of which bloom periodically throughout the growing season for long-lasting enjoyment. These shrubs attract hummingbirds, butterflies, and other pollinators.
USDA Growing Zones: 5–8
Height: 4–6 feet
Sun Exposure: Partial
‘Girard’s Hot Shot’
This evergreen azalea – a cross between R. ‘El Capitan’ and R. ‘Aladdin’ – is best suited to warmer climates because it’s susceptible to winter weather damage. Its vivid red blooms stay low to the ground and work well in the middle of a border.
USDA Growing Zones: 6-9
Height: 2–3 feet
Sun Exposure: Partial
