Watermedia Mystery: Really, What is Gouache?

March 08, 2018 5 min read

We’ve all been wooed by that stand adjacent to the watercolor paints: gouache. We bring it home and stare. What is it? Will it work with watercolor paints?

Then it sits in a drawer for a year. Maybe 10.

Time to dust it off. Because it could be real love after all.

On the surface, gouache (pronounced ‘gwash’) and watercolor seem very similar, confusingly so. But transparent watercolorist Sue Archer would never be caught dead with gouache while artists like Donna Zagotta and Carla O’Connor rely on its properties as a major part of their painting style. So what’s happening here?


Below we hope to clear up some of the confusion of watercolor vs gouache.


how to paint gouache-Understanding gouache v transparent watercolor

Can gouache be used like watercolor?

Gouache, a member of the watermedia family, can absolutely be used like watercolor. Artists can use gouache on watercolor paper and any other surface suitable for watercolor. You can use your watercolor brushes with gouache without fear of ruining them (looking at you acrylics!), and you won’t need to buy any special chemicals for clean up because, like watercolor, gouache is water soluble and can be cleaned up with water. As with watercolor, you can rewet gouache with water to make alterations or thin it with water to make it more transparent.


In fact, you can mix gouache paints with watercolor paints and use them together. Artist Donna Zagotta does. Nothing will explode, we promise.

Wait, so are gouache and watercolor the same then?

No. While you can use the same paper and brushes, gouache will handle differently than watercolor. That’s because on a structural level, it’s manufactured differently than watercolor.

How is gouache different than watercolor?

The quick overview: Gouache is opaque, matte and can be blended. Gouache dries quicker and darker than watercolor.

Here's what’s going on:

On a structural level, all paint consists of color particles (color dust) suspended in medium. Oil paint is color particles suspended in oil. Acrylic is color particles suspended in polymer. Watercolor and gouache are color particles suspended in gum arabic.


how to paint gouache - different strenghts of gouche

And not all particles are created equal.

Compared to watercolors, gouache has larger particles of pigment, and its particles are packed more tightly together. Large, tightly packed particles leave less space for light to slip through, and that’s what makes gouache opaque. Some manufacturers include a white chalk additive to further reduce transparency.

This level of opaqueness makes gouache great for illustrators who want to ensure accurate photography and reproduction of their work. That same quality makes gouache terrible for those glowing effects so sought after by transparent watercolorists.

Painters like Carl Dalio and Sue Archer reach for transparent watercolors because they want to create luminous paintings. Transparent pigments have tiny particles that aren’t packed together. This allows light to bounce through their paintings, hit the white paper and then bounce back out to the viewer’s eye, which creates spectacular luminosity.

Then why would I choose Gouache?
Artists like Sarkis Antikajian use gouache for his plein air kit because it’s easy to carry a palette (like watercolor) and he can still paint light on dark. It’s also water-based so it’s easy to clean up.


how to paint gouache - great for painting plein air

Watermedia artists Donna Zagotta uses gouache because she knows there are ways she can manipulate gouache paint that she can’t with transparent watercolor. For example, she can melt colors into one another. She does this by starting with a base color (in this case ultramarine blue.) When the color is dry she can add a second color on top.

“The first stroke down will stick,” says Zagotta in her workshop, The You Factor: Powerful, Personal Design in Opaque Watercolor.  “But the more I play with it the more it starts melting the colors that are underneath….So I’m using an undercolor and an overcolor mixed together to create the third color.”

Zagotta has two palettes. One with her transparent watercolors and one with her gouache colors. She adds white gouache paint to her transparent watercolors so that they take on gouache characteristics. (Sort of like mixing watercolor paints with acrylic paints makes them acrylics a la Nicholas SImmons’ workshop, Innovative Water Media.)

For artist Carla O’Connor, gouache is her go to watermedia because she loves the textures she can achieve. “This medium brought me full circle in my career,” she says. “I can paint with gouache much the same way as I painted in oils.”


how to paint gouache - understanding texture

“Gouache sits on the surface of your paper so it allows you tremendous freedom in lifting possibilities and corrections and changing, which then again gives more and more different textures and technique possibilities,” says O’Connor in her workshop Figure Design in Gouache: The Process.

O’Connor also loves the grays you can get with gouache. She loves the gouache grays so much that she keeps part of her palette dedicated to them.  

“I use to clean it up all the time,” she says of the lid of her palette where the greys live. “ I don’t do that anymore...I just keep adding paint to it and I can make it darker or lighter or a different color all together. But I use it for mixing all my greys.”

That grey, which she calls her Mother Color because it’s a combination of all her colors, is now a signature of her work,

Are Gouache paints just opaque watercolor?

This gets confusing because of language and how artists use terms.

Some artists refer to gouache and watercolor as totally separate media. However, some artists, like Donna Zagotta, use the word opaque watercolor to mean gouache.


how to paint gouache - Gouache v watercolor

So then when you hear artists talk about opaque watercolor they could either be referring to gouache or to particular watercolor pigments, like the cadmiums, that are naturally opaque.

How do I make my gouache transparent?

If you have a set of gouache paints, and you’d like to have transparent washes in your paintings, no need to run out to the art store just yet. The good news is that you can make almost any pigment transparent. With watercolor and gouache, you simply add more water. This creates more space between those big pigment particles and allows light to bounce back through. Just make sure to allow a layer to dry completely before going back in for a second glaze.


how to paint gouache - how to make your gouache more transparent

Does any of this matter?

Yes! (But also no.)

Artists at the level of Sue Archer, Carl Dalio, Carla O’Connor, and any of the other artists you see at CCPVideos.com are skilled and practiced enough to achieve very particular effects in their paintings. They know exactly where they want to go, and they want to use the best available tools to get there.

Carl Dalio’s paintings are all about luminosity and clean color, so he uses only the most transparent of watercolor pigments, and he cleans his palette constantly.

Carla O’Connor wants rich, greyed color and freedom to create texture that is normally not available to transparent watercolorists, so she reaches mainly for gouache. And she cleans her palette far less frequently than Dalio.

Try Some Gouache!

So the next time you’re looking for a new medium to try or are just are curious about the differences watercolor v gouache, grab some colors and start to play.


If you want some great guides in the process, we highly recommend Steven Quiller’s Water Media Foundation workshop to give you a good overview of gouache (and other watermedia). If you'd like to see how the media can be worked through an entire painting, check out  both Donna Zagotta’s The You Factor: Powerful, Personal Design in Opaque Watercolor and Carla O’Connor’s Figure Design in Gouache: The Process.


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