Lettuce is an annual plant of the daisy family, Asteraceae. It is most often grown as a leaf vegetable, but sometimes for its stem and seeds. Lettuce is most often used for salads, although it is also seen in other kinds of food, such as soups, sandwiches and wraps; it can also be grilled. To store a full head of lettuce, wrap in a damp paper towel and put the head inside a plastic bag. Store in the refrigerator. If you're storing individual lettuce leaves, spin them dry after washing and place in a lettuce keeper in the fridge. A container is best to avoid bruising and bacteria buildup. Lettuce does best in a loose, well-drained soil, with regular watering and adequate nitrogen. Whether your soil is heavy clay or a light sandy type, the incorporation of compost will often improve the growing conditions. Lettuce does best in a loose, well-drained soil, with regular watering and adequate nitrogen. Whether your soil is heavy clay or a light sandy type, the incorporation of compost will often improve the growing conditions. Lettuce is a nutritious vegetable that comes in many varieties. It's full of important nutrients, such as fiber, potassium, manganese, and vitamins A and C. Optimal soil temperature for germination: 10-22°C (50-72°F). Seeds should sprout in 7-15 days, depending on conditions. Lettuce seeds don't sprout easily when the soil temperature is over 22°C (72°F) in summer. Also known as the Goose vegetable, Tropical lettuce, Ku mak, Yao mak, Ku Mak Cai, Daun Panjang, and Sawi Rana, Indian lettuce is a general descriptor used to describe several Asian plants with leaves that vary in shape and size.