Picking saffron crocus (Crocus sativus) in autumn. The saffron crocus (Crocus sativus) flowers for two weeks in autumn and is cultivated for the red stigmas and styles that protrude from the lilac flower. Once dried these threads are used in cooking to dye food an intense yellow and flavour the dish. Around 150,000 stigmas are required to make 1 kilogram of saffron and there are just 3 stigmas per flower. Harvested by hand in the early morning before the flowers fully open, this is a very labour intensive crop requiring 3,750 hours per hectare. The plant was cultivated from the wild crocus (Crocus cartwrightianus) and has to be propagated from secondary corms because it is a sterile triploid ( 3 chromosomes ). Iran is the main grower in the Middle East but some production is made in Europe. These are in the Lot valley, France.