Jatropha curcas L. originates from Mexico and Central America and is nowadays found in the tropics all over the world. It grows as a straight trunk with thick branchlets into a bush of upto 6 m high. Although some 170 known species of the plant exist, the name Jatropha usually refers to Jatropha curcas L., also known as "physic nut" of "hedge castor oil plant". Jatropha belongs to the Euphorbia family and is a wild plant that has not been improved.
The plant and the seeds contain curcin and diterpene, which are toxic. The plant is not edible and is avoided by animals. It can live for more than 50 years. Jatropha is best adapted to the semi-arid conditions prevailing in the drier tropics, with annual rainfall ranging from 300 to 1,200 mm. The plant occurs mainly at low altitudes in the tropics from 0 to 500 m and is adapted to high mean annual temperatures (20-28 C). It can withstand slight frost and is not sensitive to daylength. Jatropha performs best on well drained soils with good aeration and is well adapted to soils with a low nutrient content. Root formation is reduced in heavy soils and the plant does not resist water ponding.
Jatropha curcas L. is not only capable of growing on marginal land, but can help reclaim degraded lands. The roots form a protection against water erosion and protect against soil erosion by run-off if planted together with lemon grass. Since the plant deters cattle and small animals, it forms a valuable protection for food and cash crops. Therefore, it is widely used in hedges. In the first half of the twentieth century, Portugal imported some 2,000 tons of Jatropha seeds yearly from the Cape Verdian islands to produce soap.
A recent publication (November 2010) on the current status of Jatropha, as additional background to our handbook, can be downloaded from Agentschap NL, please click_here.