Botanical name: Rhododendron simsii
Azalea is a popular flowering houseplant that will add a splash of color when in bloom but does not last very long under room conditions. It is only displayed when in bloom after which it is taken away until the next bloom or discarded altogether. It will thrive as a garden shrub if planted out when flowering is over. The brightly colored blooms will brighten up any dull room. To keep it in bloom for many weeks up to 3-4 weeks, keep it wet (not just moist), distinctly cool and brightly lit. Remove faded flowers promptly to encourage new blooms. Keep the plant pot-bound to encourage flowering. The blooms are terminal meaning the entire plant blooms at one time which makes a colorful display. The blooms are a profusion of shades of pink, red, white, peach, lavender or bi-colors. Azaleas are native to several continents including Asia, Europe and North America. There are over 10,000 different cultivars of Azalea.
Azaleas prefer bright light conditions but away from direct sunlight as it can scorch the leaves. Learn how to ensure your plant receives the correct light in this guide on understanding light for houseplants
Keep the soil moist at all times for Azalea and never allow the soil to dry out. Occasionally water by the immersion method as it ensures the soil is thoroughly wetted. Reduce watering during the cold period. Use chlorine-free water as the plants are sensitive to chlorine and other chemicals dissolved in water. Avoid waterlogging as it can lead to Root-rot Disease. Learn more on how to water houseplants.
Azalea prefers cool to average warmth with a minimum of 100C. Protect it from cold and hot draughts. Find out more on temperature for houseplants.
Azalea prefers moderate humidity. Do not mist the leaves as it can lead to fungal infections. Set the pot on a wet pebble tray to raise humidity.
Feed Azalea with a phosphorous-rich fertilizer formulated for acid-loving plants every 2-3 weeks during the growing season. Do not feed a plant that is in flower. Find out more on how to feed houseplants.
Repot Azalea during the growing season only when the plant is extremely pot-bound; it blooms more when pot-bound. Do not repot a plant that is in flower. Use a pot 1 size larger and one that has a drainage hole to prevent waterlogging as it can lead to Root-rot Disease. The soil should be slightly acidic, rich in organic matter and free-draining.
Prune Azalea yearly after flowering by cutting back the stems to the desired height. This will encourage growth of new stem tips from which the flowers grow which means the plant will bloom even more. Learn more on how to prune houseplants.
Azaleas can be propagated from stem cuttings but they take long to root and do not stay true to type. It is preferable to buy a plant from the breeders.
The reason for short flowering period in Azalea is hot dry air. Keep the plant away from hot air and set the pot on a wet pebble tray to raise humidity. Avoid exposing the plant to hot sun and maintain the soil consistently moist. Never allow the soil to dry out.
Yellow leaves with green veins in Azalea is a sign of a nutrient deficiency due to high alkalinity in the soil. Azaleas prefer an acidic soil.
The cause of leaf drop in Azaleas is incorrect watering; either underwatering or overwatering. Maintain the soil moist at all times and avoid waterlogging. Learn more on how to water houseplants.
Shrivelled leaves in Azalea are caused by underwatering. Maintain the soil moist at all times and never allow the soil to dry out. Thoroughly soak the soil several times a week.
Yellow leaves in Azalea are due to watering the plant with hard water. Azaleas are acid loving plants and therefore should not be watered with hard water. Use distilled or rain water only to water Azaleas.
Dry air will cause the flower buds in Azalea to shrivel, turn brown and drop. Protect the plant from draughts and raise humidity by placing the pot on a wet pebble tray.
One common disease in Azalea is Powdery Mildew where the new leaves curl, become pale, then brown and die. Discard the plant as it will not recover. Anothe common disease in Azalea is Root-rot brought about by waterlogging of the soil. Ensure the soil is free-draining and the pot has a drainage hole to prevent waterlogging.
Azaleas (Rhododendron simsii) are toxic to humans and pets. If ingested they can cause a burning sensation in the mouth, drooling, vomiting, diarrhea and lethargy. Keep these plants from the reach of children and pets.