lettuce

Cultivated annual salad plant () that produces clusters of crisp, water-filled leaves. The best-known varieties are head, or cabbage, lettuce (variety ); leaf, or curled, lettuce (variety ); cos, or romaine, lettuce (variety ); and asparagus lettuce (variety ). 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.

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