Vandaspecies

Learn more

Vanda denisoniana

Bens. & Rchb.f. 1869
Section Obtusiloba

Pure white form of Vanda denisoniana, illustrated in Motes, Gardiner & Roberts (Orchid Review 2016) and Motes (The Natural Genus Vanda 2021).
Vanda denisoniana pure white form – Motes, Gardiner & Roberts (Orchid Review 2016; The Natural Genus Vanda 2021)

Vanda denisoniana is a highly attractive species and widely represented in cultivation. Unlike most species in the genus, which are fragrant during the day, Vanda denisoniana is fragrant in the evening and morning.

It is a typical member of section Obtusiloba, characterized by broad, rounded lateral lobes. These mid- to montane species share a continuous distribution from Myanmar to Vietnam, through Thailand, Laos, and Yunnan. They are closely related and frequently confused, which has long led to identification errors.

The entire complex of taxa, including forms with spots or tessellations, has long been poorly defined and a source of confusion. Subsequently, several taxa were described, including the varieties punctata, hebraica, and tessellata.

Desirable and attractive lemon yellow flowers of Vanda denisoniana, illustrating a natural color variation within the species. This form represents one of the typical yellow phenotypes observed in both wild populations and cultivation, alongside white and greenish expressions. Also illustrated in The Natural Genus Vanda by Martin Motes (2021).
Vanda denisoniana lemon yellow flowers – natural variation (illustrated in The Natural Genus Vanda, Motes)

Vanda brunnea was described in 1868 by Heinrich Reichenbach based on plants collected in Myanmar by Charles Parish, characterized as brown and tessellated but also other forms that were lighter yellow and marked.

In 1869, Reichenbach described Vanda denisoniana from plants collected in Myanmar by Colonel Robson Benson, with white flowers and yellow-green tones at the apex of sepals, petals, and lip.

Orange flower of Vanda denisoniana showing a rare color variation in cultivation.
Vanda denisoniana orange form – rare color expression in cultivation

This complex taxonomic situation remained unresolved for a long time. Gunnar Seidenfaden was among the first to significantly advance its clarification, providing an initial framework for a more rigorous interpretation of the taxa.

Later, the study by Martin Motes, Gardiner & Roberts, The identity of spotted Vanda denisoniana (Orchid Review, 2016), provided a clearer conceptual framework, allowing better separation of Vanda brunnea, Vanda denisoniana, and the intermediate forms that had long been difficult to classify, although not considered fully definitive by the authors.

This study demonstrates that genetic introgression between Vanda brunnea and Vanda denisoniana, in both directions, explains the occurrence of spotted and tessellated flowers. These forms are best interpreted as natural hybrids, referred to as Vanda × hebraica, rather than Vanda denisoniana var. hebraica.

Within this framework, morphological variation in Vanda denisoniana can be better interpreted.

  • Pure forms of Vanda denisoniana are white to deep yellow, without spots or markings. The lip is yellow-green, broadly pandurate, with pale yellow lateral lobes at the base.
  • Forms with small black dots, very common in nature and cultivation, correspond to natural hybrids between Vanda denisoniana and Vanda brunnea, known as Vanda × hebraica, rather than true infraspecific variants (a dedicated article will follow on this blog).
  • Plants with brownish flowers, narrower and slightly twisted tepals, and a lip with a reddish-brown apex correspond to a more recently described species (2021): Vanda gardinerae (article forthcoming).
  • Vanda brunnea presents brown, strongly tessellated flowers (a dedicated article will be published soon on this blog).
Strong lemon yellow flowers of Vanda denisoniana, representing a more pronounced yellow expression within the natural variability of the species. This form illustrates the diversity of yellow phenotypes observed in both wild and cultivated populations.
Vanda denisoniana strong lemon yellow flowers – natural variation in cultivation

Several photographs illustrating pure Vanda denisoniana and Vanda × hebraica in that study are by the author of this blog and are also reproduced here. The same applies to many images published in The Natural Genus Vanda by Martin Motes.

The species was dedicated to Lady Denison (1809–1841), wife of Lord Albert Denison, an orchid enthusiast.

Spotted flower of Vanda denisoniana showing dark markings on the petals linked to natural variation.
Flower of Vanda denisoniana showing small dark spots on the petals, a character frequently observed in natural populations and cultivation, associated with introgression from Vanda brunnea.

Synonyms

Vanda henryi, Vanda micholitzii

Distribution

Mountain to mid-mountain species occurring between 450 and 1200 m elevation, found in northeastern Myanmar, Yunnan (China), Laos, northern and northeastern Thailand, and northern Vietnam.

Group of Vanda denisoniana plants for sale in a Bangkok plant market.
Group of cultivated Vanda denisoniana plants observed in a plant market in Bangkok, illustrating the species’ strong presence in horticulture across Southeast Asia.

Vernacular names

Myanmar: Thayet Htaew
Laos: Euang Nang Nouane
Thailand: Sam Poi Khun Tan
Vietnam: Lan thanh nga, Mỹ dung dạ hương

Flowers

Flowers 5–6 cm, waxy, long-lasting, pleasantly fragrant in the morning and evening. Color variation includes ivory white, golden yellow, lemon yellow, greenish, and orange tones.

Tepals are generally rounded to sub-orbicular, sometimes more expanded or almost rectangular depending on forms.

The lip is broad, with five ridges, orange-marked at the base, and strongly bilobed at the apex. The mid-lobe is yellow-green, lateral lobes large and rounded, pale yellow at the base. Spur short and conical.

White-flowered forms, often referred to as “alba” in cultivation, are not taxonomically recognized but remain highly valued horticulturally.

Inflorescence of Vanda denisoniana with flowers showing expanded, almost rectangular tepals.
Inflorescence of Vanda denisoniana showing flowers with more expanded, almost rectangular tepals, illustrating one of the morphological variations observed within the species.

Inflorescence

4–8 flowers, erect to sub-erect, 15–18 cm long.

Vanda denisoniana plant with two inflorescences showing yellow flowers and flowers turning orange.
Whole plant of Vanda denisoniana bearing two inflorescences at different stages of flower coloration, one yellow and the other turning orange. This illustrates the dynamic range of colour expression within cultivated populations.

Plant

Medium-sized in cultivation, sometimes reaching up to one meter. Leaves ligulate, recurved, and bilobed at the apex.

A relatively easy species in cultivation, mainly due to its montane origin and moderate size.

It is also used in hybridization, particularly for its characteristic fragrance and its yellow, orange, or white color forms.

Close-up of Vanda denisoniana flower lip showing morphology and ridges.
Close-up of the lip of Vanda denisoniana,
Leaf of Vanda denisoniana showing ligulate shape and bilobed apex.
Leaf of Vanda denisoniana
Cross-section of Vanda denisoniana leaf showing internal structure.
Cross-section of a leaf of Vanda denisoniana