Fennel belongs to the family Apiaceae. It is native to southern Europe and the Mediterranean region.
Fennel is widely cultivated, both in its native hábitat and elsewhere, for its edible, strongly flavoured leaves and seeds. The flavour is similar to that of anise and star anise, though usually not so strong. The taste of fennel varies from sweet to slightly bitter.
The largest quantity of herbal essential oil is obtained by hydrodistilling fresh or slightly wilted foliage just before flowering. Fruits can be distilled any time after harvest, but they must be milled or crushed and distilled immediately to avoid oil loss by evaporation. The temperature must be high enough to prevent the oil from congealing. Essential oil from different plant parts and between different regional cultivars tends to be very variable.