- The first mandarin, Citrus deliciosa, introduced to England from China in 1805, from where it spread to the Mediterranean and throughout the western world. The fruit is small to medium with a small, heavily furrowed neck and sometimes a navel. It peels very easily, the segment walls are fairly tough but the flesh is very juicy with an aromatic and sweet taste. It does not ship or store very well. Essential oils are produced from the rind and the leaves and twigs.