Azalea indica

white azalea


Azalea indica 'Alba Magnifica'

L. 1753

pronounced: uh-ZAY-lee-uh IN-dik-uh AL-buh mag-NIFF-ick-uh

(Ericaceae — the heath family)

synonym — Rhododendron indicum

(L.)Sweet 1832

pronounced: roh-duh-DEN-dron IN-dik-um

common name: white azalea

There is some doubt as to which of the two names is correct and which is the synonym. Botanically, azaleas are separated from rhododendrons by the number of stamens, the former having 5 – 7 stamens per flower, and the latter 7 – 10. Problems arise with those that have 7 stamens! The word Azalea is derived from the Greek αζαλεος (azaleos), dry, referring to the habitat of the type species Azalea procumbens. Rhododendron is from 'ροδον (rhodon), the rose, and δενδρον (dendron), a tree – the rose tree. Indica and indicum mean, as you would expect, ‘from India’.

‘Alba Magnifica’ is a well-established and well-loved hybrid. A hardy evergreen shrub with a great showy display of flowers, it looks great in a mass planting in a garden bed. It prefers a fairly acidic (pH 4.5 – 5.5 is best) and moist soil, and semi-shade. The filtering of the sunlight can be very important in tropical or subtropical regions, as the leaves are liable to sunburn.

This hybrid grows to a height of about 100 to 180 cm, with a similar spread. It has woody branching stems; the leaves are a rich green in colour, with a hairy underside. They are oval in shape, but pointed at both ends. There are clusters of infundibuliform single white flowers.

Azaleas originate from Japan, China, Korea and the highlands of Thailand, and are suited to most parts of Australia. There are 3 main groups of hybrids, indica, karume, and mollis. In most climates the indica hybrids spot flower through autumn and winter, and have their main flush of blossom in spring.

Many gardeners are put off azaleas because of their reputation for being prone to pests and diseases. The azalea lace bug does indeed like to suck sap from the leaves. The first signs that it is present are brown and silvery mottled leaves. It can be controlled by spraying at the start of the growing season, or by pruning the damaged branches, preferably after flowering. During a wet winter plants may also be affected by azalea petal blight, that causes some of the flowers to become mushy and brown. This can be controlled by spraying with a fungicide, or by simply removing the damaged flowers. The effects of petal blight can be mitigated by watering at the base of the plant, rather than by overhead sprinkling.

As with most azaleas, ‘Alba Magnifica’ can also do well in a pot. Whether in the garden or in a pot, azaleas can grow spindly, but careful pruning can remedy this.

The yellow caterpillars of the Azalea Leafminer Caloptilia azaleella are an international pest, mining the leaves of members of this genus.


Photographs taken in Nelly Bay, 2013
Page last updated 17th October 2018