The vanilla plant, which can reach up to fifteen metres in length, is a vine with green knotty, fleshy, cylindrical, and far reaching stems. They cling to trees and any other support by 2 mm diameter adventitious roots. The main stem has a diameter of one to two centimetres.
The leaves are green and evergreen growing to 15 - 25 centimetres with a width of 5 - 8 centimetres. The trumpet-shaped flowers are bright yellow and fragrant.
Stamens, style, and stigma are fused to form the gynandrium. Pollen is transferred to the stigma by hand. The wind has no pollinating action due to the arrangement of the parts of the flower.
The fruit is an elongated green pod. Pods grow on a raceme of around ten fruit of various lengths between 10 and 20 centimetres. The fruit turns yellow and brown on maturity, at which time it is harvested.
Of the hundred or so known species which are more or less localised, three have been historically identified as source of natural vanillin:
- Vanilla Pompona Shiede : mainly found in Tropical America, Brazil, Guyana, and grown in the Caribbean (Martinique, Guadeloupe, and Trinidad). As this vanilla has a very low yield, cultivation was quickly abandoned. It is better known under the name of "vanillon" or "banana vanilla" with a production of a few hundred kilos per year. The pods are short, with an average length of 10 to 12 cm, and 1-3 cm wide. Odorous principle: VANILLIN
- Vanilla Tahitentis Moore : introduced to Polynesia in 1848 by Admiral R. Hamelin. In the 50s, French Polynesia was the second top vanilla producer behind Madagascar with a production of 200 tonnes. The cultivation of this spice, penalised by the development of the global production structure and dissuasive labour costs, has steadily declined to stabilise at just a few tonnes per year. In addition, its lower vanillin content and strong aniseed aroma also encouraged user industries to turn to Bourbon or Indonesian vanilla. Tahiti vanilla is mainly used by the perfume industry in the form of extracts and in "gourmet" pods for baking. Odorous principle: HELIOTROPIN
- Vanilla Planifolia or Vanilla Fragrans : Introduced to the Indian Ocean in the late 19th century, it is the most produced and marketed vanilla in the world and is grown in Madagascar, Comoros, and Reunion (called "Bourbon vanilla" for these three origins) as well as India, Indonesia, Uganda, Mexico, and Tonga.