The primary color that is a mix of blue and yellow is green. In color theory, blue and yellow are considered primary colors, and when they are combined, they produce green, which is a secondary color. This blending illustrates the additive nature of colors in both art and design. Green is often associated with nature, growth, and harmony, representing a balance between the coolness of blue and the warmth of yellow. It plays a significant role in various fields, including environmentalism, design, and psychology, symbolizing renewal and energy.