What Is Nite Herb Nite Herb Valerian root extract 150mg is a traditional herbal medicinal product used for the temporary relief of sleep disturbances due to symptoms of mild anxiety. What Is Valerian Root Valerian is a hardy perennial flowering plant, with heads of sweetly scented pink or white flowers. It has been used as a medicinal herb since at least the time of ancient Greece & Rome, & was used as a perfume in the sixteenth century.