Which principle would involve arranging flowers of various sizes in proportion to one another?

The principle that involves arranging flowers of various sizes in proportion to one another is scale. Scale pertains to the relative size of elements in a floral arrangement, ensuring that the various components harmonize together and create a visually appealing composition. When different flowers and materials are selected, they should complement each other in size; for instance, larger blooms can be balanced with smaller ones to achieve a cohesive look that feels natural and well-thought-out.

In contrast, balance relates to the visual weight of the arrangement but does not specifically focus on size; it ensures that no part of the arrangement feels too heavy or lopsided compared to another. Accent refers to highlighting a particular element within the arrangement to draw attention, while rhythm involves creating a sense of movement through repeated patterns or colors throughout the design. Each of these principles plays a role in floral design, but scale is particularly focused on the relationship of size between various elements.