Growing Azaleas in Canberra

Azaleas are acid loving plants, and will not tolerate lime. The preferred pH is 5.5 to 6.00 in a light, well-drained soil. Eastern Australia is fortunate in that most soils are very suitable. In order to turn an alkaline soil to acidic, add aluminium sulphate or iron sulphate, or elemental Sulphur. 

Mulching, particularly during hot summer months is recommended as Azaleas are shallow rooting plants. All varieties tolerate shade positions but need adequate light to produce buds and flowers.

Fertilising of Azaleas is best done in October after flowering and again in March. Azalea and Camellia Food, and Healthy Earth are examples of suitable fertilisers. Watering must be done at regular intervals especially during Summer.

To keep your Azaleas in good shape, prune hard after flowering in late Spring and lightly again in January when buds will set, then mid March, at the latest, to tidy up shape. This will ensure a well budded, bushy plant for the main flowering time in Spring. After pruning feed with granular fertilizer and water in with liquid food for example Aquasol or Seasol.

Pest & disease management

To successfully grow Azaleas the home gardener must be aware of two problems: Petal Blight and Lace Bug. 

Petal Blight

Petal Blight is a fungal disease causing flowers to go soft and mushy and to turn brown. To prevent Petal Blight, use the fungicide, Mancozeb upon the first sign of flowers. Spray every two weeks till flowers finish.

Lace Bug

Azalea Lace Bug damages the leaves which turn a speckled silver colour. To prevent Lace Bug, spray with the insecticide, Confidor in the first week of November and the first week of January each year.

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