appearance baby-cos caesar-salad colors colours cos cos-lettuce crisp-leaves crunchy cultivars edges elongated fancy foliage food fresh gardening green greenery greens growth lactuca-sativa-longifolia leaves lettuce long-leaves plants romaine-lettuce salad salad-green salads succulent tangy tasty texture textures varieties vegetable vegetable-growth vegetables banquet Dinner fat meat meats mushroom plate polish roast salami sausage supper abstract algorithm background function math