Common Name:

General Information

Rhododendron hodgsonii is an evergreen shrub or a small tree that can gow from 3 - 11 metres tall[, , ].
The plant is harvested from the wild for local use as a source of materials. It is grown as an ornamental in gardens, valued especially for its large leaves and beautiful bark[].

Known Hazards

Although no specific mention of toxicity has been seen for this species, all parts of Rhododendron species (including the leaves, flowers and pollen) contain greater or lesser amounts of the toxic compound andromedotoxin (also known as grayanotoxin). Rarely lethal to humans (and used medicinally in some herbal disciplines), this compound causes dose-dependant overstimulation of the central nervous system with symptoms including various cardiovascular effects (mainly low blood pressure and cardiac rhythm disorders); nausea and vomiting; and a change in consciousness. The effects commence shortly after ingestion and last around two days. These effects are also transferred to honey made from the nectar of the flowers. In some parts of the world bees are used to deliberately produce a honey rich in andromedotoxin which is then eaten for its supposed medicinal, hallucinogenic and aphrodisiac effects.
In contrast to humans, many other creatures are more susceptible to the toxin and it has sometimes proved lethal to grazing animals and household pets. Some forms of honeybees are also killed by the toxin (resistant forms of the bee are used for honey production). Bumblebees are not affected, however, and are also more efficient in pollinating rhododendron flowers, so one theory is that the toxin is produced by the plant in order to favour the bumblebee and improve fertilization rates[].

Botanical References

,

Range

E. Asia - Himalayan regions of China (Xizang), eastern Nepal, Bhutan, India (Sikkim, West Bengal, Arunachal Pradesh).

Habitat

Abies forests, thickets; at elevations from 3,500 - 4,000 metres[]. Valley bottoms, on the rocky spurs or slopes of the hills, in open places, or in the gloomy pine-groves, often forming an impenetrable thicket[].

Properties

Other Uses Rating
Habit	Evergreen Tree
Height	5.00 m
Growth Rate	Slow
Cultivation Status	Ornamental, Wild

Cultivation Details

Rhododendron hodgsonii is not a very cold-tolerant plant, when fully dormant it can withstand short periods with temperatures down to about -10°c Although somewhat cold-tolerant when dormant, the flowers and young growth of Rhododendrons are very susceptible to damage by late frosts in regions where these are likely to occur after new growth has commenced in the spring[].
Rhododendron species generally succeed when grown in a non-compacted, humus rich lime free soil and a position with some shade, preferably light woodland shade. They strongly dislike soils of a dry arid nature, heavy soils or clays[]. Prefers a peaty or well-drained sandy loam[]. Succeeds in sun or shade, the warmer the climate the more shade a plant requires[]. Requires a pH between 4.5 and 5.5[].
Rhododendron species are mainly woodland species that grow well in the dappled shade and shelter given by the other woodland plants. They are surface-rooting species with a fibrous root system, however, and do not grow well close to trees that are also surface-rooting, nor do they do well with ground cover or other small plants growing over or into their roots[, ].
Plants form a root ball and are very tolerant of being transplanted, even when quite large, so long as the root ball is kept intact[].
With its large rich green leaves and its beautiful bark, this species is one of the noblest of ornamental rhododendrons[].
A very slow-growing tree[].

Edible Uses

None known

Medicinal

None known

Other Uses

The obovate leaves are around 15 - 30cm long and 7 - 10cm wide, sometimes larger. They are very leathery, the upper surface dark green and glossy, the lower surface covered with a dense, brownish-red down[]. They are used as linings in baskets, to wrap foods and also for packaging apples[].
The leaves are employed as platters, and serve for lining the baskets which contain the mashed pulp of Arisaema root (a kind of Colocass); and the customary present of butter or curd is always enclosed in this glossy foliage[].

The yellowish-white wood is close and even-grained. It is easily worked, not apt to be split, and so is admirably adapted for use in the parched and arid climate of Tibet where it is employed for making cups, spoons, and ladles, and the saddle, by means of which loads are slung upon the yak[, 146r].
The wood is used for fuel[, ].

Propagation

Seed - surface sow in a shady part of the greenhouse in late winter or early spring[, ]. Another report says that the seed is best sown in the autumn as soon as it is ripe[]. Germination is variable and can be quite slow. Prick out the seedlings into individual pots as soon as they are large enough to handle and grow the pots on in a shady frame for 18 months before planting them out into their permanent positions[].
Cuttings of half-ripe wood, 5 - 8cm with a heel, mid summer in a frame. Plant out in spring. Fair percentage[].
Cuttings of mature wood, late autumn in a frame[].
Layering in the autumn. Takes 12 months[].
Division.