Allamanda Cathartica - (Golden trumpet vine) রবীন্দ্রনাথের দেয়া নাম অলকানন্দা।

[Device used: Panasonic Lumix DMC Fz-18; Gazipur, Bangladesh /2008]

Native to South America, yellow allamanda is a climbing, vine-like shrub with striking yellow flowers. It was introduced to Queensland as an ornamental plant and is now common in gardens. [1]

Allamanda cathartica is naturally found in tropical America growing in Brazil along forest margins and water courses from sea level to an altitude of 700 m (2,296 ft). It prefers a well drained fertile moist organic rich sandy to clay loam with a ph range from 5.0 to 6.5. It grows in an open sunny position and is frost and drought tender.

The Golden Trumpet Vine is grown for its large flowers and dense foliage. It is grown over a pergola for shade or along fences for screening and used for colour in tropical gardens. It is also grown as a prostrate shrub and can be trimmed to form an informal hedge. It establishes in 2 to 3 years and is suitable for coastal regions requiring little care. Once established it has a medium water requirement, (Scale: 2-drops from 3) and responds to mulching with an occasional deep watering during dry periods. [2]

The flowers are bright yellow or sometimes pink, bell-shaped with 5 rounded lobes.
The leaves are large, lance-shaped, glossy green and occur in opposite pairs or whorled in groups of three or four, measuring about 10cm long and 3-4cm wide.
The fruit are prickly capsules that contain winged seeds.

All parts of the plant considered to be toxic although evidence is poor. If eaten, it may cause diarrhoea and vomiting. Skin contact may cause dermatitis. [3]

Medicinal

An infusion of leaves, in moderate doses, is an excellent cathartic; in larger doses it is purgative and violently emetic [360]. A decoction of the leaves, in small doses, is used as an antidote to poisoning and as a treatment for colic [360].

The bark and latex, in small doses, are considered cathartic; in large doses, poisonous[360]. A decoction of the bark is used as a hydragogue [360]. [4]

History of Introduction and Spread

Herbarium collections and botanical surveys suggest that A. cathartica was introduced in the Caribbean region by at least the mid-nineteenth century. It was first reported as early as 1864 by A.H.R. Grisebach as a “cultivated plant” in Jamaica, St Kitts, St. Vincent, and Antigua (Grisebach, 1864). Later, in 1873, F.A. Sauvalle reported this species for Cuba and in 1879 H.F.A. Eggers reported it as a “cultivated plant” on the Virgin Islands (Eggers, 1879). In Puerto Rico, the oldest record of this species comes from Bello Espinosa (1881) where the species is regarded as cultivated and spontaneous. In 1888, Stahl reported this species as naturalized throughout the Antilles. At the start of the twentieth century this species is described as a “cultivated and escaped” by Ignaz Urban (Symbolae Antillanae vol. IV) for the islands of Cuba, Jamaica, St Thomas, St. Kitts, Antigua, Guadeloupe, Martinique, St. Vicent, Barbados, Trinidad and Puerto Rico (Urban, 1905).

In Australia, A. cathartica was first recorded as naturalized in 1945, and by 1992 it was recognized as a weed in Queensland (Queensland Department of Primary Industries and Fisheries, 2011). In Costa Rica, the oldest record of A. cathartica comes from a herbarium collection made in 1900 in Nicoya (Guanacaste) and by 1938 this species is described as a common ornamental plant in gardens throughout the country (Standley, 1938). Later, in 2005, J.F. Morales described this species as “escaped from cultivation and naturalized” along the Atlantic Coast mainly in areas near Tortuguero National Park and in the rest of the country along forest edges in wet forests, secondary forests, and swampy areas near rivers and lagoons (Morales, 2005). [5]