Growing Azalea Bushes in Your Garden

Perfecto Mundo® Pink Carpet dwarf azalea. Photo by: Proven Winners.

When to plant:

Plant azalea shrubs during the cooler months of spring or fall to avoid heat or cold stress.

Where to plant:

Choose a full to partially sunny site with rich well-draining soil.

How to plant:

Loosen soil in planting area and amend with compost or other organic matter. Dig a planting hole slightly wider and deeper than the root ball. Make several slits in the root ball. Place the plant in the hole with the top of the root ball slightly above the surrounding ground to allow for settling, and fill in around the sides of the root ball. Do not cover the top of the root ball with soil. Cover the root ball with soil and tamp down. Water thoroughly and keep soil evenly moist until established.

Spacing:

Allow enough space around plants to accommodate their mature size.

For containers:

Make sure pots have adequate drainage holes. Use a high quality all-purpose potting mix.

Watering:

Azaleas have shallow roots, so are more sensitive to water stress. Keep soil evenly moist but not soggy. Overwatering can cause root rot or other diseases. Increase watering during hot or dry spells to prevent wilting, leaf curl, or brown foliage. Containers dry out more quickly, so will need more frequent watering.

Amendments and fertilizer:

In spring, apply a fertilizer especially formulated for acid-loving plants, such as azaleas, camellias, and rhododendrons, according to package instructions.

Mulch:

Add serveal inches of organic material around the base, but not up to them stem, to suppress weeds, retain moisture, and provide additional nutrients. Replenish mulch annually. Pine needles make an excellent mulch for azaleas because they add acidity to the soil as they break down.

Pruning:

Azaleas look best when they are allowed to keep their natural shape and size. Prune azaleas just after flowering. Cut back errant branches and shape as needed. This is also the time to shear formal hedges. Cutting back plants in summer or fall will result in the loss of the next year’s flower buds. Remove dead or diseased growth as soon as it appears.

Diseases & pests:

Azaleas are prone to a number of pests and diseases, though healthy plants are more resistant. Pests include aphids, spider mites, scale, whitefly, borer, thrips, nematodes, weevils, and lace bugs. Diseases include powdery mildew, rust, leaf spot, crown or root rot, petal blight, leaf gall, chlorosis, canker, and dieback.

For borders and landscapes: Use as hedging or screening, in foundation plantings, mixed or woodland borders.

For slopes and hills: Mass along a slope or hillside for erosion control.

For containers: Smaller specimens can be planted in containers by themselves or in combination with other plants for multi-seasonal interest.

Here are a few tips for incorporating azaleas into your garden:

• Use a medium sized variety as formal clipped hedging along a street, sidewalk, or fence or to divide garden rooms.
• Combine with a mix of other deciduous and evergreen shrubs for a four-season foundation planting.
• Plant alongside other flowering shrubs that bloom at different times for a continuous display of color.
• Underplant with spring blooming bulbs such as crocus, daffodil, and muscari for an early season color display.
• A larger evergreen variety can be massed along a property line for year-round privacy.

Companion plants: Azalea companion plants include abelia, dogwood, ferns, hosta, sedges, Japanese andromeda (Pieris), witch hazel, hellebores, and snowdrops.

What is the difference between an azalea and a rhododendron?

Azaleas and rhododendrons are both classified in the genus Rhododendron, though are differentiated by several characteristics. Azaleas are generally smaller and may be deciduous or evergreen, while rhododendrons are strictly evergreen. Leaves of azaleas are thinner, often with a soft, hairy texture. An azalea flower typically has 5 to 6 stamens, while a rhododendron bloom usually has 10 or more stamens. Azaleas produce 1 to 3 flowers per stem, while rhododendron blooms occur in larger clusters.

Are azaleas poisonous?

Azaleas contain grayanotoxins, which can be extremely harmful to pets and livestock. Ingesting even a few leaves can cause serious injury. If you suspect your pet has ingested any part of the plant, take them to an emergency veterinarian immediately. Make sure to take a sample of the plant along for positive ID. Plants can also be harmful to small children; go to an ER immediately if your child ingests any part of the plant.

Are azaleas deer resistant?

Deer find the leaves and stems of azaleas to be appealing and can cause significant grazing damage to plants.

What aren't my azaleas blooming?

There are a number of factors that can keep azaleas from blooming:

• Pruning at the wrong time. Azaleas bloom on old wood. If they are pruned too late in the season, next year's buds can be sacrificed.
• Using the wrong fertilizer. A fertilizer that is too high in nitrogen will put the plant's energy into producing foliage, not flowers.
• Cold weather. Harsh winter weather can cause damage to azalea branches where the buds are held.
• Not enough sunlight or water. Make sure your azalea is getting at least 6 hours of sunlight each day and is watered regularly.