Watercolor Techniques: Overlaying Washes (Glazing)

Glazing layers of the same color to darken value. Lisa Marder

Learning to paint washes is fundamental to watercolor painting. A wash is watercolor paint diluted with water. You can control the value, or tone, of the wash by controlling the ratio of paint to water - the more water, the lighter the value will be. To cover a large surface with a flat, or even, wash you want to use a large amount of the paint and water mixture to keep the edges blended.You can also overlay transparent washes, also called glazing.

Applying a glaze on top of the same color darkens the value. The more glazes you add, the darker the value will become. 

Note: Edges can be hard or soft. A hard edge shows a distinct and even line between colors or strokes. A soft edge is a blurred or blended, often indistinct, line between colors or strokes. In watercolor, a hard edge can be achieved by painting wet paint onto a dry surface (wet on dry). A soft edge can be achieved by painting wet paint onto a wet surface. (wet on wet)

Overlaying Washes of the Same Color (also called Glazing)

One way to darken the value of watercolor is to overlay washes. Controlling value is important to being able to define form and create the illusion of depth and space on a two-dimensional surface. This method uses the transparency of the watercolor by overlaying washes of the same color. In this method you allow the paint to dry, and then add successive layers of the same color, letting each layer dry before painting another layer.

Each additional layer darkens the value of the color. Note that letting the paint dry between applications leaves a hard edge between layers.

See Watercolor Techniques: Washes to learn about flat and graded washes

Try overlaying washes with a number of different paint colors and on different papers to see how many layers you can get and how dark a value before the paint and paper start to degrade.

Start with a flat wash of your lightest value covering the whole page. After that is completely dry, leave about an inch at the top and cover the rest of the surface with another flat wash of the same color. Repeat that process as you work your way down the surface, leaving part of each preceding layer showing. 

Overlaying Washes of Different Colors (also called Glazing)

You can also overlap washes of two colors to change the tone and hue of the underlying color. The transparency of the top color with the underlying layer creates a third color. With this technique it is essential to let the paint layers dry before applications to avoid the colors running together.  It is also important to know how colors will interact with each other. To test this, I recommend painting a grid of lines. First paint a vertical line of each color you want to test, and let the lines dry. Then paint a horizontal line of each color over the vertical lines. You will see the new color created at the intersection of the vertical and horizontal lines. See Marion Boddy-Evans' article How to Test if a Paint Color is Opaque or Transparent for an example of a grid of colors.

Painting the grid will also enable you to see which colors are more transparent and which are more opaque.

 Watercolors can be transparent, translucent, or opaque. Read Characteristics of Watercolor Paint to read more about transparency and other characteristics.

See a step-by-step demonstration of painting leaves using the watercolor glazing technique in Step-by-Step Demo: Painting Glazes with Watercolor.

More: Read about two-color washes and variegated washes.

More: Read about the different types of watercolor paint - pan, tube, liquid - in Types of Watercolor Paint.