Saffron is a spice used in cooking, medicine and as a dye. Saffron is recognised as the most expensive spice by weight. This is mostly due to the fact that saffron originates from the Saffron Crocus, a flower with red stigmas. There are three stigmas in one flower, and the dried stigmas create what we know as saffron. That is not a lot of saffron per flower, thus making it expensive. There are several cultivars all over the world, each country having its own variety of saffron, Iran being the largest producer.
The Saffron Crocus' themselves require moisture, and do not fare well in shade. They flourish best in Mediterranean maquis climates, although they can survive temperatures as cold as -10° Celsius, and could even survive a short time in the snow.
Saffron, as a spice, can yield many uses, which is why it is so desirable. Medicinally, it is supposedly helpful with depression, mild Alzheimer's, and as a PMS symptom reliever. Culinarily, it has a bitter hay-like fragance, and adds a golden yellow tinge to food. In powder form, it is red, regardless of the fact that it produces a yellow pigment. It is traditionally used in Persian, Arab, Central Asian, Pakistani, Indian, European and Turkish cuisines, and is a prominent spice in Hinduism.