Cress is a group of peppery greens more commonly grown and used in Europe in salad mixes, sandwiches, soups, and garnishes. There are three main types of edible cress, each unique in shape, texture, and growing requirements. Watercress is by nature a semi-aquatic plant long cultivated in milder regions of the world as a perennial, and increasingly indoors as well, most often hydroponically. Garden cress is the fast-growing form most typically produced in controlled-environment agriculture. Upland (or land) cress, has an extended harvest window under average field conditions, and is slower growing and sharper in flavor than other cresses, as it has a lower water content.