The saffron spice comes from the flower of the Crocus Sativus, so it is a member of the crocus family. The flower is more usually called the saffron crocus. This plant grows wild in parts of Asia but has been cultivated in Europe since ancient times, at least since the days of Ancient Greece.

The saffron spice is harvested from the stigma (the little tip at the end of the carpel, or seed-producing organ; the stigma is the part of a plant that gets pollinated). Each saffron crocus has only a small number of stigmas, and each one has to be collected by hand. This is a delicate and very labour-intensive job, and that is why saffron is the most expensive spice in the world.

Saffron has also been cultivated in colder countries throughout history; some UK gardeners grow their own saffron, though an individual gardener could only expect a small crop.