Outsidepride Watercress Herb Salad Seeds - 10000 Seeds Watercress herb seeds are grown as a perennial plant in USDA zones 5 - 11 across the U.S. Also called water radish and water rocket. This perennial is used for culinary purposes in the kitchen grows approximately 12 - 24 inches tall. Nasturtium Officanale is the Latin name for watercress which will blossom with white flowers. These heirloom seeds are non gmo and open pollinated. Watercress is cultivated as both a culinary herb as well as a medicinal herb. It is a succulent, leafy plant that thrives in marshes, bogs and water gardens. Plant 15 - 20 seeds per plant to get a robust plant in your herb garden.