The two most common azalea hybrids are the Indian azalea, or Rhododendron simsii, and the Japanese azalea, or Rhododendron obtusum. Both are dwarf shrubs that have single and double flowers in red, pink and white, although the Japanese cultivar has smaller blooms. A third hydrid called Belgian or pot azalea is gaining popularity as a gift plant because unlike the first two, the pot azalea remains green all year round and can be made to bloom anytime under controlled conditions. Regardless of variety, azaleas have common requirements for light exposure, temperature, water and fertiliser.
Grow azaleas in acidic or coniferous soil. Compost may also be used.
Keep azalea plants in bright, half-shady locations away from direct sunlight.
Water regularly to keep soil evenly moist. Soft water is recommended but not necessary.
Provide cool temperatures. Azaleas prefer cool temperatures at 10 to 15.5 degrees C (50F to 60F). In the winter, they prefer temperatures between 3 and 15 degrees C (37F to 48F). Indian azaleas can be grown in a moderately warm climate of up to about 20 degrees C (68F).
Keep air humidity high. Regular misting is recommended, especially during the flowering season.
Feed lightly with an acid-based fertiliser in the spring or autumn. Azaleas do not need fertiliser if organic mulch or compost is used as a growing medium.
Prune after flowering to define the size and shape. Azaleas typically bloom in the winter or early spring and keep blooming for several weeks. Trim after all the flowers are spent.
Propagate from softwood cuttings taken in the spring or summer. Lightly dip the cuttings in rooting hormone to initiate growth.
Azaleas are sensitive to light, water, temperature and humidity. Too much light burns the leaves; underwatering causes leaf loss; hot and dry air shortens the flowering period.
The flowers of the azalea are toxic. Keep out of reach of children and pets.