Gouache & Watercolor

Gouache: What is it? And how do I pronounce it?

For starters, it’s pronounced “guh-wash.” Throw this one into casual conversation and people will be very impressed.

The traditional way to create white space in a watercolor painting is called “reserving,” which means leaving the paper free of paint where you want light space to appear. Another, more modern way to create light in your piece is incorporating white pigment into your watercolor palette.

When you combine white pigment with watercolor paint, you’re officially using gouache. Gouache paints are essentially an opaque version of watercolors. A paint color is opaque when it hides what’s underneath—when it lacks translucency. White pigment slowly lightens a watercolor pigment, fading it out by reducing its translucent quality and increasing its opacity. I like to think that adding gouache paint to watercolor paint is like adding cream to black coffee. Gouache works beautifully to add highlights or create light in a dark space. It’s also super useful if you would like to add a light layer on top of a dark-toned watercolor piece.

Most watercolor kits come with a white color called Chinese White. It is only semi-opaque, but when combined with other tubes of paint in your watercolor kit it will get you close to gouache. You can also purchase a tube of white gouache, which will enable you to create your own gouache on your palettes.

Gouache is unique because its opacity is like that of oil or acrylic paint, yet it is pliable and water-soluble like watercolors. Gouache is also commonly known as “opaque watercolor.” Prized for its versatility, gouache dries quickly but can be reactivated with water and altered after it dries. However, unlike watercolor, gouache allows you to add color and actually cover up what’s underneath. It’s the best of both worlds. One thing to remember is that gouache usually dries to a slightly different shade because of its increased opacity: in most cases, lighter tones will dry lighter and darker tones, darker.

You can use all sorts of techniques, from drybrush to translucent washes, with gouache. All of the watercolor techniques we cover in the book are applicable to your gouache painting journey as well. Just like in watercolor, you don’t want to layer gouache too thickly, as it may crack if it becomes too heavy. I water mine down considerably and treat it just like watercolor, as far as the paint-towater ratio I load onto my brush. A little gouache goes a long way!