The watercolor technique Variegated wash is a process for blending two or more colors together on very wet watercolor paper using the wet-on-wet technique. This method is normally used for painting a blended background on a full sheet of paper. The resulting effect resembles a sunset.
Mix each watercolor separately with a sufficient amount of water.
Wet the paper with clean water using a large brush or sponge.
Tilt the paper on a board or easel.
Quickly apply the lighter watercolor across the top of the paper and let the paint flow down to the middle.
Turn the paper upside-down.
Apply the second watercolor across what is now the top of the paper, and let the paint flow down and blend into the first watercolor. You can adjust the amount of blending by the amount of time the paper is tilted.
Always allow the watercolor to blend by itself over the wet surface. It should look very free-flowing.
You can slow down the variegated bleed by laying the paper down flat.
For covering large areas, use a one-inch flat brush or an oval “wash brush” (also called a “mop brush”). To paint smaller areas with a variegated wash, use a round brush size 10 or larger.
Controlling the brush and the painting speed is important. The wetness of the paper needs to be consistent until the desired area is covered with the variegated wash. The tip of the brush should lightly touch the paper and move across the paper in a smooth, horizontal stroke.
When the variegated wash is complete, leave the paper flat until it has dried completely.
Optional: If desired, a second variegated wash can be applied over the first. After the first wash is completely dry, rewet the paper with clean water and apply watercolor as before to achieve greater depth and luminosity. Let the second wash dry completely.
Then proceed with painting the rest of your watercolor composition.
Recommended
Use 140 lb cold press archival 100% cotton rag watercolor paper. It is advisable to stretch the watercolor paper first to prevent it from buckling if you plan to cover the paper with a wet-on-wet variegated wash. To avoid stretching the paper, I recommend using a watercolor paper block.