Which type of flower is characterized by erect, tall spikes of blooms and is often used to create a sense of length in floral arrangements?

The type of flower characterized by erect, tall spikes of blooms that create a sense of length in floral arrangements is line flowers. These flowers are known for their linear shape and vertical growth, which allows them to accentuate the height and structure of an arrangement. They help to create a framework that can guide the eye and add dynamism to the overall composition.

Line flowers are essential in floral design as they provide movement and lead the viewer's gaze throughout the arrangement. Some common examples of line flowers include delphiniums, snapdragons, and gladiolus. Their distinct ability to rise above other elements in the arrangement contributes to a balanced and harmonious look, making them an invaluable tool for florists when designing visually impactful displays.

In contrast, mass flowers are typically rounded and used for filling space and adding color, while filler flowers serve to fill gaps and add texture without dominating the design. Form flowers have unique shapes that serve as focal points but do not provide the same linear effect that line flowers do.