The plant, originating in Central America , whereas it has been spread to other tropical and subtropical countries as well  and is mainly grown in Asia and in Africa, where it is known as Pourghère. It is used as a living fence to protect gardens and fields from animals. 
It is resistant to a high degree of aridity and as such does not compete with food crops.wastelands and grows almost anywhere, even on gravelly, sandy and saline soils. It can thrive on the poorest stony soil and grow in the crevices of rocks. Complete germination is achieved within 9 days. Adding manure during the germination has negative effects during that phase, but is favourable if applied after germination is achieved. However, it is usually multiplied by cuttings, because this gives faster results than multiplication by seeds.
For learning about our trees & plants, please visit/ join Google e-group (Indiantreepix) http://groups.google.co.in/group/indiantreepix?hl=en
For my Birds, Butterflies, Trees, Lanscape pictures etc., visit http://commons.wikimedia.org/wiki/Special:Contributions/J.M.Garg