Azaleas are beautiful spring-blooming shrubs that add a pop of color to any garden. Their showy flowers come in a wide range of colors including white, pink, red, purple, yellow and orange Azaleas are native to several parts of the world, including North America, Europe and Asia This popularity has led to azaleas becoming a beloved garden plant.
When azaleas are given as gifts or bought from nurseries, they are often kept inside as houseplants. But a lot of gardeners aren’t sure if these indoor azaleas can be successfully moved outside. The answer is yes, with some important tips to follow.
When is the Best Time to Plant Azaleas Outdoors?
Timing is crucial when planting azaleas outdoors. Azaleas should only be planted outside once they have completely finished flowering, which is usually in May. Planting too early while azaleas are still in bloom can shock the plant.
Ideally, azaleas should be planted outdoors in spring after the last frost has passed. This gives them time to establish roots before the heat of summer arrives. If planting later in summer, be sure to water frequently as azaleas prefer consistently moist (but not soggy) soil.
Selecting the Right Location for Azaleas
Azaleas thrive in sites with dappled sunlight or light shade. They enjoy morning sun with afternoon shade. When planting azaleas, don’t put them in full sun, because the leaves can get burned.
Well-drained, acidic soil is ideal for azaleas. Amend clay soils with compost or peat moss to improve drainage. If needed, use sulfur or aluminum sulfate to lower the pH of the soil.
Plant azaleas near trees, shrubs or structures that can act as a windbreak. Where necessary, protect the plant from strong, cold, north-easterly wind.
Digging a Proper Planting Hole
There should be about twice as much space between the holes as there is deep. The width is important to encourage horizontal root growth.
Create a mound of soil in the center of the hole and place the azalea on top. This will allow the top of the root ball to sit just above ground level, preventing crown rot.
Backfill the hole with the excavated soil, amended with compost or peat moss. Water thoroughly after planting to remove any air pockets.
Ongoing Azalea Care
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Water 1-2 times per week, providing 1-2 inches of water each time. Water at the base, not overhead.
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Use 2 to 4 inches of pine bark or wood chips as mulch around azaleas to keep the soil moist. Leave space between mulch and stems.
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Fertilize in early spring and midsummer with an acidic fertilizer formulated for azaleas.
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Prune immediately after flowering by selectively removing deadwood and shaping.
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Watch for common azalea pests like lace bugs, spider mites and aphids. Treat promptly to avoid damage.
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In very cold climates, protect in late fall with a loose burlap wrap around plants.
Transplanting Tips for Indoor Azaleas
To successfully transition an indoor azalea into an outdoor garden follow these tips:
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Harden off indoor azaleas by placing them outdoors in a sheltered location for 7-10 days before planting. Gradually increase light exposure.
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Water thoroughly before transplanting and again after planting. This encourages new root formation.
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Prune back leggy growth by 1/3 to compensate for reduced root system.
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Plant in a location with afternoon shade. Dappled sun is ideal for newly planted azaleas.
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Stake for support if needed while the plant establishes over the first year.
With proper timing, care and technique, gardeners can enjoy the gorgeous blooms of azaleas planted outdoors for years to come. Pay close attention in the first year while new plantings establish roots. But soon your gifted indoor azalea will be thriving as a spectacular addition to your outdoor garden.
Yes, azaleas can be planted outside with great success by following a few simple guidelines. Proper timing in spring, site selection, amending soil, planting techniques and ongoing care will help ensure a smooth transition from indoor to outdoor growing. With the right conditions, azaleas will flourish in gardens and provide stunning floral displays year after year.
Overwintering azalea indoors
Azalea houseplants require a cool and bright location in winter. The temperature may then drop to as low as 8 °C. At this time, it is important to ensure enough light. Before you put the azalea in its winter place, remove all dead flowers and fruit sets. Then, in the spring, place it outside so that it can thrive again in the next flowering season.

Overwintering: which azaleas are hardy?
Not all azalea species are hardy. Frost hardiness is basically determined by whether the species is deciduous or not. Deciduous species are mostly intended for outdoor cultivation and are also hardy. This means that they can simply stay outside in the winter. Evergreen azaleas are intended for indoor use and are not frost hardy. They need to be overwintered in a cool and bright place. Japanese azaleas and diamond azaleas, on the other hand, are outdoor azaleas that retain most of their foliage even in winter. Like deciduous azaleas, they are frost hardy.
How to Grow & Care for Azaleas – Keep Your Plants Healthy & Blooming Year After Year
FAQ
Where should you not plant azaleas?
It is best not to plant near concrete foundations or other concrete materials because the concrete makes the soil alkaline (pH of 6 or higher), which is bad for rhododendron and azalea growth. People often use aluminum sulfate to lower the pH of soil, i. e. make it more acidic, for growing hydrangeas.
How do you keep azaleas alive outside?
The perfect spot for an azalea is in the semi-shade or shade. Ideal soil: azaleas enjoy moist, humus-rich acidic soil. Cut off dead flowers. In no time at all, you’ll have a better-looking plant.
Is there a difference between indoor and outdoor azaleas?
Indoor azaleas are not frost hardy like outdoor azaleas and rhododendrons. This means that they should not be planted permanently in frost-prone areas once they are done flowering. However, they can be kept and grown on as pot plants for flowering in future years.
Where is the best place to plant azaleas?
The best place to plant azaleas is in a location that provides partial shade or filtered sunlight, ideally with morning sun and afternoon shade. They also thrive in well-drained, acidic soil.