Romaine lettuce is known for its long, crisp leaves that form a tall head. It is typically grown in the cooler months in fields, using traditional farming methods such as tillage, planting, irrigation, fertilization, and pest management. The lettuce is usually harvested by cutting the entire head off at the base, then transported to a processing facility for washing, packaging, and distribution. Some farmers may also use greenhouse production methods, where the lettuce is grown in a controlled environment, which can allow for year-round production and can be used to protect the plants from pests and extreme weather conditions. In recent years, the use of hydroponics systems has also become more popular for lettuce production, which involves growing plants in nutrient-rich water rather than soil. However, relatively little commercial scale hydroponic or greenhouse production is carried out in the U.S. as compared to field production.
