Curry Leaf leaves are used fresh, dried, whole and crushed. The curry leaf is used especially often in South Indian cuisine.
The little curry tree usually grows wild at about 1500m above sea level. Murraya koenigii or Bergera koenigii is native to tropical and subtropical parts of Asia. Today, it is widely found in Sri Lanka, Nepal, Myanmar, Thailand and China.
see Anne Iburg "Dumont little spice encyclopedia", Eggolsheim, Dörfler Verlag GmbH