HOW TO GROW AZALEAS
Azaleas are amongst the most beautiful flowering shrubs for the garden, celebrated for their masses of vibrant blooms in a variety of shades. Native mainly to Asia, they are widely grown around the world, and many improved hybrids have been developed to thrive in local gardens. Azaleas are related to rhododendrons, and although they prefer cooler, moist conditions, the right choice of hybrid can perform beautifully in warmer regions too.
These evergreen neat, rounded shrubs bloom during late winter and spring, bringing a stunning splash of colour to shady garden beds, courtyards and containers. Azaleas grow best in slightly acidic soil, rich in organic matter, and they thrive in dappled shade rather than full sun. With the right preparation, they are easy to maintain and reward you with spectacular displays year after year.
PLANTING PROCEDURE
– Select a position with morning sun and afternoon shade or dappled light under trees.
– Prepare the soil by digging deeply to a depth of at least 400mm.
– Work in generous amounts of acid compost and well-rotted pine needles or leaf mould to enrich the soil.
– Add a small handful of agricultural lime-free bone meal or superphosphate per planting hole.
– Ensure the soil drains well. Azaleas dislike “wet feet.” In heavy soils, raise the bed slightly or plant into large containers.
– Dig a hole slightly larger than the root ball of the plant.
– Place the azalea at the same depth it was growing in the pot — planting too deep may cause root problems.
– Backfill with soil and gently firm down.
– Water thoroughly after planting.
FERTILISING AND CARE
– Mulch the root zone with pine bark, pine needles or compost to keep the soil cool and moist.
– Apply a fertiliser formulated for acid-loving plants in early spring and again after flowering (look for 5:1:5 or an azalea/camellia fertiliser).
– Lightly prune after flowering if needed to maintain shape. Avoid hard pruning into old wood.
– Water regularly during dry periods, especially when in bud and bloom.
– Azaleas in pots need more frequent watering and feeding than those in the ground.
PESTS AND DISEASES
Azaleas are generally hardy but can be affected by the following:
– Azalea lace bug – causes mottled, pale leaves. Spray with an appropriate insecticide.
– Red spider mite – leads to yellowing and fine webbing on leaves. Control with a miticide.
– Root rot – usually caused by poor drainage. Improve soil conditions or plant in raised beds/containers.
– Petal blight – flowers turn brown prematurely. Remove affected blooms and spray with fungicide if needed.
GARDEN USES
– Excellent in semi-shaded beds and woodland-style gardens.
– Superb as container specimens on patios or in courtyards.
– Ideal for creating colourful borders under trees.
– Combine well with camellias, hydrangeas and ferns for a lush, cool-climate look.
– Can be mass-planted for a dramatic spring display.
SUMMARY
– Azaleas provide a spectacular show of flowers in late winter and spring.
– They grow best in dappled shade, in moist, acidic, well-drained soil.
– Mulch well and water regularly, especially during dry spells.
– Fertilise with an acid-loving plant food twice a year.
– Deadhead and prune lightly after flowering to keep plants neat.
SHOPPING LIST
– Acid compost and leaf mould or pine needles for soil preparation.
– Bone meal or superphosphate for strong root growth.
– Pine bark or pine needles for mulch.
– Azalea/camellia fertiliser.
– Healthy azalea plants in a variety of colours.
– Decorative pots or planters for container displays.
– Watering can or hose for regular watering.
