Kindly sponsored by
Peter Norris, enabling the use of The Rhododendron Handbook 1998
New article for Trees and Shrubs Online.
'Rhododendron tuba' from the website Trees and Shrubs Online (treesandshrubsonline.
Shrub to 5 m, usually terrestrial, young stems sparsely scaly. Leaves 4–9 × 2.5–5 cm, elliptic to broadly elliptic, the apex broadly acute often somewhat acuminate, the margin flat, narrowly cartilaginous in the upper part, the base truncate or rounded occasionally weakly cordate; the upper surface at first scaly but quickly becoming glabrescent, the midrib depressed above, grooved near the base, lateral veins 6–8 pairs slightly depressed; lower surface with the midrib broadly raised beneath, the laterals smooth or very slightly raised, scales moderately dense and persistent, substellately lobed, brown, the centres somewhat impressed. Flowers 4–7 per umbel, horizontal to half-hanging; calyx variable from a low almost glabrous disc to occasionally having long laciniate lobes; corolla white with a pink tube, trumpet-shaped but somewhat curved, 6.5–9 × 2–3 cm, obscurely scaly outside; stamens 10, rather unequal and grouped in the mouth of the flower; ovary both hairy and scaly, style hairy and scaly in the lower half. Royal Horticultural Society (1997)
Distribution Papua New Guinea SE, Mt Dayman
Habitat 2,500–2,700 m
RHS Hardiness Rating H2
Conservation status Least concern (LC)
Very similar to R. rhodoleucum from which it is distinguished by its non or hardly cordate leaves, a longer petiole and smaller anthers (petioles 2–4mm instead of 0–1mm in R. rhodoleucum and anthers up to 2.5 v. more than 3.5mm in R. rhodoleucum). It is also very similar to R. armitii which is distinguished by its larger leaves and much longer petioles, more than 6mm long. Royal Horticultural Society (1997)