When you are first learning to paint in watercolor, you don’t think much about edges. You’re mostly concerned with control. You consider the painting a technical triumph when the dark green leaves you’re painting don’t run into your roses or your trees bleed into your barn. To avoid these disasters, you may even leave thin, white borders around every object or allow each area to dry before you paint an adjoining area. Although you didn’t make any mistakes, the resulting painting had a hard-edged, “itchy” quality to it. The edges throughout were monotonously similar. You were probably unaware of how variation in edge can serve both as a descriptive device and as an effective design element in your painting.

Descriptive Edges
We can most clearly detect the texture and form of an object—whether it’s rough or smooth, round or square—at its outside edge or at the edge of the shadow on it. You don’t have to spend the entire afternoon painting every leaf on a tree with a #6 brush to show it’s bushy. Nor do you have to get the Saran-wrap or a credit card out every time you paint a rock. You can quickly and effectively suggest the texture and form of an object by making its edges descriptive.

Edge As A Design Device
Our eyes and brains are very selective: we focus on the things that interest us and everything else becomes soft and vague. Unlike a camera, our eyes can’t bring the foreground, middle ground, and background into sharp focus at the same time. We can only focus on one selected area at a time. As painters, we select the area (or areas) we want viewers to see by employing hard and soft edges in our composition to create focus. By softening (or “losing”) edges between objects or areas (for example, the foreground and background), we create passages that allow the viewer’s eye to move through the design. By sharpening (or “finding”) edges we attract and hold the viewer’s attention on areas of importance.