Azaleas and Rhododendrons at Downside Nurseries

On a dull wet day like today, what better to lift your spirits than catching sight of some of the beautiful Azaleas and Rhododendrons we have in Bay 8

Native to Asia, Europe and North America, they can be either evergreen or deciduous.  They both belong to the genus Rhododendron and are close enough botanically that Azaleas are identified as subgenera.  All Azaleas are Rhododendrons, but not all Rhododendrons are Azaleas!

The name Rhododendron comes from the Ancient Greek rhódon – Rose; déndron – Tree. In Chinese culture, the Azalea is known as the “Thinking of Home Bush” although the actual name Azalea comes from the ancient Greek “Azaleos” meaning dry.

Both azaleas and rhododendrons do best in well-drained acidic soil with a pH of 4.5 – 6.0 and prefer a cool site with filtered sunlight. Morning sun with afternoon dappled shade works best but if your site is full sun, then the deciduous forms will tolerate full sun better than the evergreen varieties.

They all have quite a delicate shallow root system, so need a good watering during dry spells, but take care not to overwater or you can have problems with root rot. Mulching will help protect the root system, and mixing in composted bark before planting will help the increase the drainage and the organic content of the soil. They also prefer not to be watered from overhead – which can lead to foliar diseases – and would much rather not have “tap” water.

In the UK they tend to flower in spring and early summer, from buds formed the previous year. If you need to prune them then the best time to do so is just after flowering is over, as pruning after July may result in no flowers at all next spring!