Which method refers to placing similar materials horizontally on top of each other in floral design?

The method that involves placing similar materials horizontally on top of each other in floral design is known as terracing and layering. This technique creates depth and dimension in arrangements by stacking elements in a way that mimics the natural layering found in landscapes. By organizing materials horizontally, designers can achieve a visually balanced and harmonious look that enhances the overall composition.

Terracing typically involves creating a step-like effect where each layer is slightly different in height or size, contributing to a sense of movement and flow in the arrangement. Layering, on the other hand, focuses on building up materials to create a more complex and textured design.

The other methods mentioned do not focus on this horizontal stacking technique. Framing typically involves using materials to create a boundary or outline for an arrangement, while the waterfall technique is characterized by flowing, cascading elements rather than the horizontal stacking seen in terracing and layering. Light intensity, unrelated to the physical arrangement of materials, refers to the brightness of light in relation to plant growth and does not pertain to structural design methods.