The Makrut Lime, also called Kaffir (an ethnic slur) Lime or Thai Lime, is from South East Asia where its leaves are the key ingredients in green curries. The tree is easily identified by its hourglass shaped double leaves. The fruits are round, wrinkled and bumpy, and can reach the size of a pool ball. The fruit, rind and leaves emit an intense almost mineral citrus odor and fruits turn yellow when ripe. The tree is thorny (like most citrus) and grows between 4 to 11 meters tall. Trees can withstand short bouts of frost but prefer sub-tropical and tropical climates.