Sweet potato stems are usually long and trailing and bear lobed or unlobed leaves that vary in shape. The flowers, borne in clusters in the axils of the leaves, are funnel-shaped and tinged with pink or rose-violet. The edible part is the much-enlarged tuberous root, varying in shape from fusiform to oblong or pointed oval. Root colours range from white to orange and occasionally purple inside and from light buff to brown or rose and purplish red outside. The pulp consists largely of starch, and orange-fleshed varieties are high in carotene.