Large erect epiphytes or lithophytes with numerous thick roots and long fibrous leafy stems, unbranched or sparsely branched from near the base. The thick, crowded or well-spaced flat or terete leathery leaves are arranged in 2 ranks. Inflorescences are racemes with few moderately small to large often round flowers. The flowers, which last many days, have the labellum fixed to the base of the column or the short column foot. The labellum is 3-lobed with a short pouch-like basal spur. The column is short and lacks a column foot or has a very short one.
Significant Generic Characters
Epiphytic orchids; plants large, erect; roots numerous, thick; stems long, fibrous, unbranched or sparsely branched from the base; leaves flat or terete, crowded to well spaced, arranged in 2 ranks , much longer than wide, leathery; inflorescence racemose, few-flowered; flowers moderately small to large, lasting many days; labellum firmly attached to the base of the column or the short column foot; lamina 3-lobed, with a short pouch-like basal spur; lateral lobes horizontal; column short, lacking a foot or with a short foot; pollinia 2, sessile on a stipe.
Size and Distribution
A genus of about 50 species distributed in India, China, Malaysia, Philippines, Indonesia, Timor, New Guinea and Australia where there is 1 non-endemic species . It is restricted to the Iron Range (12º38’ S) and McIlwraith Range (13º34’ S) on Cape York Peninsula. State occurrence: Queensland.
The native species of Vanda grows on trees in rainforest at low to moderate altitudes, usually in brightly lit situations where there is abundant air movement. Plants often perch high on a tree trunk with the thick white roots spreading over the bark. Occasional plants occur on rocks. The climate is tropical and the majority of rain falls during the summer wet season (December to March), with the remaining months much drier and having sporadic or intermittent rain.
Seasonal Growth: Vanda plants grow mainly during the spring and summer months and are relatively quiescent for the remainder of the year.
Flowering: The native species of Vanda flowers in spring and summer.
Hybrids: Natural hybrids involving the native species of Vanda are unknown.
The name Vanda is based on a Sanskrit word for Vanda roxburghii.
Perennial, evergreen, epiphytic, lithophytic or terrestrial herbs, monopodial. Roots numerous, thick, elongate, much branched, mainly adherent. Plants large, unbranched or sparsely branched from the base, usually erect. Stem relatively thick, long, fibrous, leafy throughout. Pseudobulbs absent. Trichomes absent. Leaves lasting several seasons, flat or terete, distichous, sessile, crowded to well-spaced, spreading widely, much longer than wide, coriaceous; base sheathing the stem, imbricate with its neighbour, persistent after leaf abscission; margins entire or undulate; apex entire or unequally emarginate. Inflorescence lateral, racemose, few-flowered. Peduncle shorter or similar to than the rhachis. Rhachis straight. Floral bracts small, scarious, partly sheathing the base of the pedicel. Pedicel long, merging with the ovary. Ovary short, straight. Flowers resupinate, small to large, opening sequentially, stalked, lasting many days, cream, reddish, yellowish or blue. Perianth segments relatively thick-textured, spreading, narrowed at the base, margins often undulate. Dorsal sepal free, subsimilar or different to the lateral sepals. Lateral sepals free, subsimilar or different to the dorsal sepal, usually flanking the labellum. Petals free, narrower than the sepals. Labellum stiffly attached to the base of the column or the vestigial column foot, markedly dissimilar in size and shape to the sepals and petals, calcarate. Labellum lamina 3-lobed, with a short basal spur; spur parallel with the column, conical or laterally compressed, blunt; lateral lobes small to large, horizontal; midlobe large, porrect, bifid, the lobules often decurved. Spur basal (see labellum lamina). Callus consisting of low fleshy keels, sometimes also flanges flanking the spur orifice. Nectar unknown. Column short, stout, porrect from the apex of the ovary, lacking free filament and style, fleshy, straight. Column wings small. Column foot absent or vestigial. Pseudospur absent. Anther terminal, incumbent, 2-celled, persistent, smooth, with a large decurved rostrum. Pollinarium present. Pollinia 2, orange, hard, waxy, sessile. Stipe short, broad. Viscidium large, at an angle to the stipe. Rostellum small to large. Stigma entire, concave. Capsules dehiscent, elongate, glabrous, porrect; peduncle not elongated in fruit; pedicel not elongated in fruit. Seeds numerous, light coloured, winged.
Within the Vandeae, Vanda is distinguished by; large plants; long flat or terete leaves; few-flowered racemes; labellum fixed to the column base or vestigial column foot; lamina 3-lobed, with a short cylindrical basal spur; callus of low keels; column without a foot or with a vestigial foot and, 2 sessile pollinia.
Vanda W.Jones ex R.Br. in Edwards’s, Bot. Reg. 6: 506 (1820).
Dockrill, A.W. (1967). Australasian Sarcanthinae. The Australasian Native Orchid Society, Sydney.
Dockrill, A.W. (1969). Australian Indigenous Orchids. Volume 1. The Society for Growing Australian Plants, Halstead Press, Sydney.
Dockrill, A.W. (1992). Australian Indigenous Orchids. Volume 1 & 2. Surrey Beatty & Sons in association with The Society for Growing Australian Plants, Chipping Norton, NSW.