Species of the Month – July 2016
Holcoglossum amesianum (Rchb. f.) Christenson
Holcoglossum amesianum belongs to the genus Holcoglossum. The name is derived from the Greek word holkos – strap and glossa – tongue, referring to the strap shaped lip of the type species. It is also known as ‘pine needle orchid’ in many parts due to the terete leaves resembling pine needles. The genus was established in 1919 by Rudolf Schlechter. The species is named after American Botanist Ames in 1900. Later in 1982 four species were recognized. Subsequently, Christenson revised and came out with eight species. The World Check list recognizes about 14 species. 
Somewhat this unique flowered species though relatively easy to grow is not very common in collections as it is slow bloomer. It’s uniqueness in the plant kingdom is the way it gets pollinated by itself. It resembles more of Vanda and has a synonym as Vanda amesiana. Till recently, this has been classified as a Vanda.
Distribution: This lovely terete leaved orchid is mainly distributed in the tropical montane forests of India (Assam), Myanmar, Cambodia, Laos, Vietnam, China and Thailand as an epiphyte on trees and rocks.
Plant: It is a medium sized monopodial with terete leaves. The stem is long and leafy with coriaceous straight or channeled tapering terete dark green leaves lending it a unique charm. The plant produces bloom in fall and winter on a simple or branched axillary racemose inflorescence. Flowers are ovate – and has several fragrant flowers which opens slowly thus extending the entire flowering time. The flowers are beautiful with pink, purple and white flowers. The unique feature of this plant is the pollination. The plant does not depend on any mode of pollination either insects or wind. It is observed that the plant fertilizes itself by removing the anther cap and the pollen twisting itself so that it lodges on the stigmatic surface to enable fertilization. This feature is so exclusive that flowers may not even transfer pollen to other flowers on the same plant.
Culture: This grows in its habitat as an epiphyte or a lithophyte. Plants require intermediate temperatures and need bright light like that of Cattleyas. Under cultivation, plants can be best on mounted for good results. They can also be planted in baskets and in pots with well drained media. On mounting plants should be watered regularly. Be careful with over watering in case it is potted. It really likes intermediate temperatures during summer and will not mind a cool winter. It needs bright and strong light for better growth and flowering. As the plant is vandaceous in nature without pseudobulbs, they need regular and frequent watering with good drainage when potted. During the growing period a balanced fertilizer such as 19-19-19 at the rate of 1 gram per liter will benefit the plant. Plants are known to perform well when mounted than potted.
Few crosses and hybrids have been produced with Holcoglossum amesianum as parent.
Vandirea ‘Newberry Jasmine’ is a primary hybrid between Holcoglossum amesianum x Sedirea japonica. Another cross of Holcoglossum amesianum and Ascocentrum pusillum is also produced.
The species can be grown under Bangalore conditions and flowers well if some care is taken.
References:
1. Holcoglossum amesianum – https://en.wikipedia.org/wiki/Holcoglossum_amesianum
2. The Bizarre Sex Life of an Orchid – www.livescience.com, Planet Earth. June 20,2006
3. American Orchid Society, 2009, James Osen
Article and Photos by: Dr. K.S. Shashidhar