Watercress is a small, semi-aquatic plant that occurs naturally along streams and in other moist areas of Europe and Asia. It is also cultivated elsewhere. In the US, for instance, it is commercially grow in Huntsville, Alabama, which is affectionately credited as being “the watercress capital of the world.”
The powdered Watercress has all the pungency of its relatives in the mustard family due to the presence of the enzyme myrosin.