How to Mix Colors

Whether you paint with watercolor, acrylic, gouache or any other pigment type for that matter, how to mix colors is a fundamental skill. Mixing pure saturated colors (those containing only two primary colors) requires a palette of two sets of primary colors.

  • A warm and a cool red
  • A warm and a cool Yellow
  • A warm and a cool blue.

We can then use the primary colors that lean towards the secondary we are mixing, thus keeping traces of the third unwanted primary out of the mixture.

How to Mix Colors

Using two of each primary avoids the problem of contaminating our secondary mixtures with the third primary. eg. Mixing green from Lemon Yellow and Phthalo Blue means our green wont contain red. If we were to mix green using Ultramarine Blue or Cadmium Yellow the resulting color would contain traces of red and not be a pure saturated green.


Usually we don’t work with pure, saturated colors but an understanding of how to mix colors to achieve pure clean saturated hues helps even when most of our work employs compound colors (colors containing traces of the three primaries)

Accurately mixing colors is nowhere near as difficult as you would imagine. Sure it requires a little practice, but it is a skill that can be quickly mastered. Mixing colors requires a simple understanding of the color wheel – most mixing involves pulling a color away from its present hue. To do this requires the addition of its complementary or opposite color. All you really need to remember are three complmentary combinations

  • Red-Green
  • Yellow-Violet
  • Blue-Orange

If a mixture is leaning too much toward any of these six hues, simply add a little of the appropriate complementary then reassess.

How to Mix Colors

A simple example

swatch To mix this color we first have to decide which color or hue it is closest to. For this color blue is about the closest. blue We start with a patch of Ultramarine, but because the color we are after is not a pure, saturated blue we must add a little of its opposite or complementary – orange mix2 We will add Alizarin Crimson and Cadmium Yellow to make the blue less saturated. Adding the Alizarin makes the mixture very dark. We can add some white to make the tonal adjustment before adding the Cadmium Yellow mix3 The addition of Titanium white has moved the mixture close to the correct tone but the color is now leaning towards purple. To neutralise the mixture further requires the complementary of purple – yellow mix4 A small amount of Cadmium Yellow neutralises (or desaturates) the color giving us a slightly darker tone of the blue/grey we are after. mix5 A little more white and we have our color. This demonstration was done with oil paint to show the effect of white. To do the same with watercolor, once the color is correct it is just a matter of adding more water to dilute the mix and allow more white paper to show through.
No matter what pigment is used to mix colors, the transfer of tube pigments to mixing palette should be done in small incriments, gradually easing the mixture towards the required color.


How to Mix Colors – Notebook Exercises 

These exercises will not only improve our control of tone and sharpen our color mixing, but also improve our brush control. To get the most out of the exercises, keep these little squares as precise and accurate as possible.


Brush - 1/4″ Flat

Colors – Ultramarine Blue, Phthalo Blue, Indian Yellow, Burnt Sienna, Alizarin Crimson

Tonal Steps

Controlling tone, with watercolor, is simply a matter of adding water to lighten the tone. With Acrylic, Oil or Gouache adding white to the mixture is the easiest way to lighten the tone.  This exercise is a great way to discover exactly how much water or white paint is necessary to produce the tone required. Mixing Colors - Tonal Gradation Exercise Draw a series of seven adjoining squares with a hard pencil so the lines are barely visible. What we want to do is paint a gradation of tones from black on the left to white on the right. It sounds easy, but we want the tonal steps between each square to appear equal. Make a dark mixture of Ultramarine Blue and Burnt Sienna. Keep it as neutral as possible – not tending towards blue or towards Burnt Sienna. Start with the dark end of the scale. Unless you are using oil paint, let each square dry before moving on to the next. Watch as the paint dries, you will find it becomes lighter in tone. This must be taken into account as you paint each square. You will probably find you need to do this exercise three or four times before you can get an even gradation from start to finish. Mixing Colors - tonal exercise A 1/4″ flat brush lets you make nice square corners and straight even lines. Turn you paper around so you use the tip of your brush for the straight lines and corners.


Mixing Color Gradation

All the saturated colors appear around the outside of the color wheel. Saturated colors are either primary colors or a mixture of no more than two primaries. Compound colors are a mixture of three primary colors, they are all the browns, Khakis, and earth colors

Mixing Colors - Complementary Colors, color wheel

Colors directly opposite one another on this 12 part colour wheel are Complementary Colors


For this exercise we are going to mix a gradation of compound colors. We will go from one side of the color wheel to the other, between two saturated, complementary (or opposite) colors. Again, we want the gradation to be as even as possible across seven steps. mixing colors - gradation exercise This graduation takes us from red – orange (Indian Yellow and Alizarin Crimson) in equal color changes to green – blue (Phthalo Blue). Mix up enough Alizarin Crimson and Indian Yellow to complete the exercise before you start. This will ensure consistent color. The middle square should be as neutral as possible with warm colors on the left and cool colors on the right.


Impact Through Contrast and Saturation

For this exercise we are going to draw up a grid of small squares and create a design using various mixtures of a pair of complementary colors. We want to achieve a feeling of depth in our design. We will do this by using lighter, cooler, less saturated colors to recede and warmer, more saturated colours to come forward. We will also establish a center of interest in our design by positioning the most saturated colors and greatest tonal contrast in the appropriate place. I have used Yellow / Violet as my complementary pair but you can use any pair of complementary colors you like. mixing colors exercise Allow one color to dominate. In this example the dominant violet recedes and the contrasting saturated yellow jumps forward. The strong tonal contrast between the dark violet square and the pale yellow square immediately draw attention, establishing a center of interest. The saturated yellow squares in this area help to reinforce the center of interest No matter what you like to paint, pure design experiments like these free you from the influence of a subject. This lets you concentrate on the abstract nature of composition and design, which is, after all, the foundation for any successful painting.


Color Matching

For this exercise we will cut out 6 flat colored squares from old magazines, paste them in our note book then draw six similar sized empty squares beside them. In these empty squares we will try mixing colors to match our cut out colored squares.

mixing colors - cutouts

Do this exercise five of six times and you will have no trouble successfully mixing any color


Color Mixing Tips

  • Have plenty of paint squeezed onto your palette
  • add small amounts of paint when adjusting your mixture
  • Dark mixtures of watercolor are easier to achieve if you avoid rinsing your brush between colors
  • To match color requires the correct tone (lightness or darkness) as well as the correct color
  • Mixing practice improves your ability to notice subtle influences making up a color



Author: John Lovett


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