Azaleas can give months of flowering pleasure from winter to summer, but as with most plants, the best results require a little bit of attention. Watering should be done on demand and the plants kept moist, but be careful not to overdo it, especially in autumn and winter as azaleas need less water as the weather cools. Never water over the buds or flowers as this can cause fungal problems that result in a shorter flowering at best, and no flowering at worst. Although Autumn conditions are not as conducive to "petal blight" as are the warm days of late Spring, it may be necessary to use Zayleton to control these problems if they occur at any time. Generally though, if overhead watering and torrential rain are avoided (Good luck with the latter), and dead flowers are picked off from time to time (put them in the bin not the garden), there is nothing to stop a wonderful display for many spring weeks, providing conditions remain fine.
As far as fertilising of Azaleas (and for that matter most plants) is concerned, monthly applications of Harvest or a Fertiliser for acid loving plants, as well as a measure of Osmocote, Organic Life or Cow manure every three or four months, should be all that's required to keep your plant in good shape. Remember not to use granular chemical fertilisers on azaleas in Autumn and Winter as you may destroy the Spring flowers. "Azalea & Camellia food" can be used after flowering to encourage new growth, but only sparingly on established plants in the ground, and never on plants in pots!
If repotting your azalea, use an excellent potting mix such as “Pot Power” that has premium ingredients, extra slow release fertiliser, water storage granules, wetting agents, and even anti fungal agents. Planting an azalea in a cheap potting mix is a complete waste of money, and although Pot Power costs more than cheaper mixes, it lasts 5 times as long, so is actually much cheaper in the long term anyway!
If you are repotting an old plant that is "pot bound" (i.e. the roots are densely packed and growing in a circle), then be sure to "tease" the roots with a small fork, so that they will stop growing in a circular fashion and grow out to the edge of the new pot.
If planting azaleas in the ground, find a well drained position, and don't hesitate to add All in One Compost, a small amount of cow manure and Organic Life, for some extra organic richness. When repotting after flowering, it's an ideal time to give your Azalea a haircut to encourage bushy new growth for the next set of flowering. Azaleas must rate as the easiest plant to prune as they invariably re-shoot no matter how hard you prune, and there are up to 1000 dormant nodes per inch, so they will generally reshoot from wherever you cut them back to! (although a number one buzz cut is not recommended) After flowering finishes is the best time to prune or shape your plant because you don't lose the beauty of the flowers, but any time of year is suitable, with the exception of the dead of summer when they may suffer sun scorch if pruned. In heatwave conditions a spray with Droughtshield or Envy before the heat will reduce transpiration (and therefore sunburn) dramatically.
The Rutherford hybrids, "Rose Queen", "Rose King", "Snow Prince" and "Snow Queen" are all excellent varieties, whether grown in containers or in the garden, and are amongst my favourites for their durability and reliability. Also terrific in autumn is "Dancer", the hard to find magnificent salmon-pink flowered variety that never seems to disappoint. "Dancer" has compact, bushy growth, and lovely dark green, semi-gloss leaves that set off the flowers beautifully. Unlike some varieties, it is hardy in ground or pot.
Kurume azaleas are the smaller style azaleas with hundreds of tiny flowers; the two best in our experience being Kirin (bright pink) and Christmas Cheer (red of course but it flowers in spring not Christmas!). Gumpo azaleas are the lowest growing azaleas, come in white, pink and two tone, but in our experience in the warmer areas of Sydney, Gumpos add their new growth in spring before the flowering, meaning the flowers are more often than not hidden from view.
The single flowered large growing azaleas are as tough as any plant in the garden, and reward with a spectacular display in spring. Alba magna (white), Splendens (salmon pink), and Alphonse Anderson (2 tone pink) are our favourites, and all can grow 2m high * 1.5m wide. At Honeysuckle Park we grow “standard” azaleas (bare stem with rounded head on top), and find Alba magna and Alphonse Anderson do extremely well.
Azaleas grown in shade can be prone to Lace Bug (results in silvery leaves especially near the base), and occasionally suffer from mites. Less common are the effects of White Curl Grub, sun scorch and fungal problems (including leaf gall). Whatever the plant disease problem, please bring in a bring a fresh sample of leaves and flowers, (in a zip lock bag please) to us for accurate diagnosis, as we know how to fix all Azalea problems, usually without the need of an Undertaker. Whilst photos and emails are useful, 3 dimensions is easier!
Pictured: An Azalea with chronic lace bug damage, easily treatable with Imidacloprid spray and tablets. Click on the pictures for a closer look.
Copyright asserted by Peter Thorburn, Honeysuckle Garden. Not to be reproduced in whole or in part without written permission.