Which color is most effective for depicting distance when painting landscapes in watercolor?

In watercolor painting, blue is the most effective color for depicting distance in landscapes. The reason for this lies in the principles of atmospheric perspective, where colors perceived at a distance become cooler and less saturated due to the scattering of light and the presence of air. Blue hues evoke a sense of depth and tranquility, mimicking how distant objects appear less vibrant and more muted than those in the foreground.

When depicting landscapes, artists often use blue tones to represent mountains, skies, or distant bodies of water, reinforcing the illusion of depth. This is especially effective when combined with warmer colors in the foreground, creating a sense of layering and dimensionality.

While yellow, red, and green each have their own importance in landscape painting, they do not traditionally convey the same sense of distance as blue does in this context. Yellow tends to evoke brightness and warmth, red can be quite bold and attention-grabbing, and green is often used for foliage and vegetation in the foreground rather than distant landscapes. Thus, blue is the color that best represents the idea of distance in watercolor landscapes.