Rhododendrons are woody plants with showy flowers and attractive foliage. As ornamental plants, they are treasured for their flowers which come in all hues and colors of the rainbow. The flowers vary greatly in size – from tiny thimbles to trumpets-like ones that measure up to 20 cm long. The trees, too, vary in size – from dwarf shrubs to 4-storey tall giants.
There are 900 species of the genus and a majority of them are found in the colder regions of the Northern Hemisphere, especially in the Himalayan Regions of Nepal, South China and North India. No species have so far been found in Africa or South America. In Australia, only one species has been recorded so far.
Rhododendrons found in the tropics belong to the category vireya. There are about 300 species of these in South East Asia. Half of them, approximately 150 species can be found in the higher mountains and hills of New Guinea. Borneo has about 50 species, and 35 of them can be found in Sabah – 25 of which are found on the slopes of Mt Kinabalu alone. Sabah can also lay claim to having 12 species that cannot be found anywhere else in the world.
The species found in South East Asia are characterized with having ‘scales’, mainly on their leaves. Similar ‘scales’ can also be found on other parts of the plants such as the stem, calyx, pedicels, ovary, style and the outside of the corolla. Besides being helpful in the identification of the species, the scales also act as shields to protect the young developing leaves from the harsh radiation of the sun.
Rhododendrons are propagated from seeds, cutting or layering. Most vireya rhododendrons have long tailed seeds which help them to go great distances when carried by the wind. Vireya Rhododendrons grow well in areas with high atmospheric moisture and in acidic and peaty soils.
Most Malaysian Rhododendrons are mountain plants. Though many of them are epiphytes – living on other trees – a few can be found on rocky grounds on steep ridges.
Of the species featured four are native to Peninsular Malaysia, namely Rhododendron Malaya-num, Rhododendron jasmine-florum, Rhododendron scortechinii and Rhododendron pauciflorum. The rest are native to Sabah and Sarawak.
Rhododendrons found in the tropics belong to the category vireya. There are about 300 species of these in South East Asia. Half of them, approximately 150 species can be found in the higher mountains and hills of New Guinea. Borneo has about 50 species, and 35 of them can be found in Sabah – 25 of which are found on the slopes of Mt Kinabalu alone. Sabah can also lay claim to having 12 species that cannot be found anywhere else in the world.
The species found in South East Asia are characterized with having ‘scales’, mainly on their leaves. Similar ‘scales’ can also be found on other parts of the plants such as the stem, calyx, pedicels, ovary, style and the outside of the corolla. Besides being helpful in the identification of the species, the scales also act as shields to protect the young developing leaves from the harsh radiation of the sun.
Most Malaysian Rhododendrons are mountain plants. Though many of them are epiphytes – living on other trees – a few can be found on rocky grounds on steep ridges.
Of the species featured four are native to Peninsular Malaysia, namely Rhododendron Malaya-num, Rhododendron jasmine-florum, Rhododendron scortechinii and Rhododendron pauciflorum. The rest are native to Sabah and Sarawak.
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