In floral arrangements, which type of flower is typically used to establish the skeleton outline of the design?

Line flowers are used to establish the skeleton outline of a floral design due to their elongated and linear form. These flowers typically have tall, straight stems and bold shapes, which help create the overall frame or structure of the arrangement. By providing vertical and horizontal elements, line flowers guide the viewer's eye throughout the design and add dimension.

In contrast, mass flowers are usually chosen for their fullness and visual weight, used to create focal points and fill larger areas within the arrangement, but they do not primarily provide the structural framework. Filler flowers serve to fill in gaps and add texture and color; they complement the arrangement but also do not create the foundational outline. Greenery contributes to the design by adding texture and can support the structure but is not as effective as line flowers in establishing the skeleton of the arrangement.