Which technique is NOT commonly used in watercolor painting?

Blending is not commonly considered a fundamental technique in watercolor painting. In traditional watercolor practices, artists often utilize techniques that involve the manipulation of the wetness and thickness of the paint. Wet-on-wet allows for soft edges and fluid transitions between colors, creating a smooth and often unpredictable appearance. The dry brush technique employs a dry brush to create texture and detail, allowing for more control over the application of pigment on paper.

The salt technique, where salt is sprinkled on wet paint to create unique textures as it absorbs moisture and alters the pigment distribution, is also a well-known method in watercolor. While blending can occur in watercolor painting, it typically requires precise control and can be less commonly emphasized compared to more distinctive techniques. Therefore, out of the mentioned options, blending stands out as the technique that is less commonly used in watercolor art.