Boston Butter Lettuce has loose, wavy, cupped leaves. The broad, soft, green outer leaves are thick and frilled at the edges, encompassing more tightly bound, yellow tinted leaves in the center of the head. Together they form a rosette pattern of leaves that are wide and have a smooth, silky consistency with a uniform crunch. Boston Butter Lettuce is tender and crisp with a sweet, nutty, and mildly astringent flavor.