Watercress

It is impossible to imagine spring without watercress, without its peppery flavour that stimulates your nose with the pure power of vitamins. Green for go!  
Watercress was initially harvested in the wild, but has been cultivated since the early 19th century. It has long been a good friend to humanity as a fabulous source of precious vitamins and minerals. Originally used as a medicine (and in magic), it gradually came to be seen as a foodstuff. In France, watercress is primarily grown in the Ile de France region (particularly Essonne), in specially designed ponds of carefully controlled running spring water. Its attractive dark green leaves are then harvested by hand.

A Gourmet's notebook