The azalea question

Sunday, 27 September 2009

The azalea Alba Magnifica

To grow azaleas or not to grow azaleas - that is the question that plagues me every September. Wherever I look, there are big mounds of azaleas(Rhododendron, Evergreen Azaleas) in full bloom, reminding me of gorgeous nineteenth-century crinoline ball gowns. They have such an abundance of flower: in pinks, white, mauve, purple, salmon and red, each one exquisite, with silky petals, long delicate stamens and dainty freckles.

My earliest love affair with a plant involved a handsome specimen of an azalea called 'White Prince', whom I met in a supermarket near to where I worked. I soon became addicted to them and ended up with a rainbow of azaleas in my young garden. One of the first gardens I ever visited - created by two delightful elderly sisters - was comprised mainly of azaleas, as were many traditional gardens of the time: clipped into hedges, standards or topiary shapes, or used to create a pretty woodland setting with Camellia, Magnolia and Japanese maples, and under-planted with bluebells and annuals such as Primula and forget-me-nots.

An azalea suffering from petal blight

So why do I now ponder whether to grow azaleas or not? It is the ghastly aftermath of their flowering that causes my dismay. When the party is over, the frocks turn to rags. Petal blight - a fungal disease of azaleas, unknown in my early gardening days - has become entrenched in our gardens in recent years and transforms the flowers into a hideous mush. The petals dry to an ugly brown colour and cling on to the shrub. The sheer number of flowers on each bush then becomes a total liability, because every single one of them becomes infected. Spores fall to the ground beneath the plants and reinfect the flowers in the following spring. Although the disease can be contained to some extent by avoiding overhead watering, and by picking off and destroying all the dead flowers, only chemical spraying of the unopened buds with a fungicide such as Bayleton can give full control of the problem. At this time, I thank my lucky stars that I don't have any azaleas, apart from two ancient specimens at the top of my driveway.

As summer arrives, the plants are further attacked by various insect pests, such as two-spotted mite, lace bug, leaf miner and thrip, which disfigure the leaves and give them a forlorn and neglected appearance. Various chemical sprays on a regular basis are recommended by gardening gurus to counteract all these problems. In these water-conscious times, the need of azaleas for moist (though well-drained) soil is another issue which gives pause for thought. A further concern is that most azaleas are pretty dull dogs for the rest of the year.

The azalea Alphonse Anderson

Some of the fancier compact cultivars also seem harder to establish in a garden setting than the tough old tall, single-flowered cultivars, which can grow 2m tall - such as white 'Alba Magnifica', pink 'Alphonse Anderson', mauve 'Magnifica Rosea', lilac 'Mauve Schryderii' and salmon 'Splendens' - and seem to need less watering and pampering once they have settled in. However, there are good performers amongst the smaller types, including pink 'Kirin' and 'Rose Queen', scarlet 'Redwing' and my old friend, 'White Prince'.

It is difficult to balance the beauty of azaleas in full bloom with the problems of cultivating them successfully. Perhaps the answer is just to have a few azaleas if you choose to grow them, so that watering and spraying are manageable. Or maybe grow some in pots (especially if they are the smaller fancy cultivars) so that they can be put out of the way when they start to look revolting. Hard pruning after flowering of the taller, tougher types will help to remove much of the petal-blighted material. Maybe we also simply have to accept that the price of the dazzling spring display is a less than perfect plant at other times of the year. Visiting a garden full of azaleas when they are at their peak and standing in admiration may be almost as good as (or even better than!) growing them for oneself.

Brunfelsia australis

Another option is to look for other sources of spring colour in Sydney gardens. Chinese lanterns (Abutilon x hybridum cultivars, ht 1-2m) are at their peak in late winter and early spring, in colours of pinks, orange, yellow, white, red and tangerine. Fringe flower shrub (Loropetalum chinense, ht 1.8m) is smothered in dainty cream or pink strap-like blooms; yesterday-today-tomorrow bush (Brunfelsia australis, ht 2.4m) has round purple flowers changing to blue and then white as they age. A compact version called 'Sweet Petite' is only 1m tall.

Spiraea cantoniensis

The may bush (Spiraea cantoniensis, ht 1.8m) has cascading branches smothered in posies of tiny white flowers, while Rondeletia amoena (ht to 3m) has clusters of pink flowers. The mist flower (Eupatorium megalophyllum, ht 1.5m) sports huge fluffy heads of purple flowers even in quite dense shade. All of these plants grow easily, and without the need for pesticides, in Sydney gardens!