There are several hundred varieties of lettuce The four most general classifications include "butterhead," "crisphead," "leaf," and "Romaine " The darker green outer leaves contain the most vitamins
A lettuce is a plant with large green leaves that is the basic ingredient of many salads. Cultivated annual salad plant (Lactuca sativa) that produces clusters of crisp, water-filled leaves. The best-known varieties are head, or cabbage, lettuce (variety capitata); leaf, or curled, lettuce (variety crispa); cos, or romaine, lettuce (variety longifolia); and asparagus lettuce (variety asparagina). Head lettuce is further divided into butter heads and crisp heads (e.g., iceberg lettuce). In the U.S, large-scale farms grow mainly crisp-head varieties, shipping them nationwide. Small-scale, local farmers raise leaf and butter-head varieties. Lettuce is an early annual crop that grows best in cool weather and with ample water. Though usually consumed in salads, it may also be cooked