- Rhododendrons
Rhododendrons with their trusses of flowers and often leathery looking leaves, are a well known flowering plant of cool climate gardens. There are between 800 and 900 different wild kinds of rhododendrons, as well as thousands of hybrids.
Rhododendrons range in size from tiny shrubs such as Rhododendron ‘Cilpinense’, R. lutescens and R. spinuliferum, with its red firecracker-like flowers, up to the impressive tree rhododendrons from the rainforests of the Himalayas in western China which reach 20-30m (up to 100′) tall. One such large form is R. macadeanum, which has clusters of large yellow flowers.
Growing rhododendrons
Rhododendrons grow well in cool places and mountain areas and are frequently seen in gardens in these districts. Admirers of these plants who visit the mountains to see spring gardens often return to their homes by the coast or in other parts of Australia wishing they could grow similar specimens in their own gardens.
There are a number of varieties that will grow right down to sea level in places such as Sydney and even further north but will also grow well in cool districts.
Most of the rhododendrons that do well in mild to warm climates are hybrids of Rhododendron arboreum, a species which comes from relatively low altitude areas in the Himalayas. Another is the attractive lavender-flowered Rhododendron ponticum. This is a wild species which has become naturalised in Britain, where it is something of a weed, but in Australia it will grow well in milder parts of the country even beside the sea.
Recommended warm climate tolerant rhododendron cultivars include:
‘Boddaertianum’ – white flowers
‘Broughtonii’ – crimson flowers
‘Elegans – rosy crimson flowers
‘Ivery’s Scarlet’ – a bright, pillar-box red flowered cultivar
‘Sir Robert Peel’ – deep rose pink flowers (this cultivar will grow as far north as Brisbane).
Rhododendron vs azalea
Gardeners can be excused for being confused about the difference between azaleas and rhododendrons. All azaleas are in fact true rhododendrons. In general those plants which flower across the top are referred to as azaleas, and those that flower in groups called trusses are deemed rhododendrons. The most commonly grown rhododendrons in Australian gardens are evergreen azaleas once referred to as Azalea indica.
Further information
Our segment was filmed at Mount Tomah Botanic Garden, Bells Line of Road, Mt Tomah, NSW, 2758. The garden, which is about 90 minutes from Sydney in the Blue Mountains, is open daily from 10am to 5pm (closed Christmas Day). Phone: (02) 4567 2154.
Rhododendrons can also be viewed in gardens in the cooler parts of Australia including The National Rhododendron Gardens, The Georgian Road, Olinda, Vic, 3788. Phone: (03) 9751 1980. This garden, which is now managed by Melbourne Parks and Waterways, was developed by the Victorian branch of the Australian Rhododendron Society (see contact details below). It is situated in the Dandenong Mountains about one hour from Melbourne.
The Australian Rhododendron Society Inc. produces an annual newsletter and has members from around Australia. There are branches in each state. For membership details or to find your local branch contact:
Barry Stagoll (Secretary)
170 Knees Road, Park Orchards, Vic, 3114
Phone: (03) 9844 1558. Membership: $20 a year.
Further reading
Gardening with Rhododendrons: A Complete Guide by Murray Richards (Florilegium, 1994, $45 rrp).
Growing Azaleas and Rhododendrons by Geoff Bryant (Simon & Schuster, 1995, $19.95 rrp).