John Hughes, “Autumn on the Sleeping Indian,” oil — example of graying down colors

“When mixing colors for the landscape, artists need to be quick on their feet,” says John Hughes. “Outdoors, where the light and shadows are in constant motion, it’s important to be able to mix a color intuitively.”

On Mixing Colors and Harmony

by John Hughes

This week’s article delves further into the “Painter’s Tool Box of Expression.” 

When mixing colors for the landscape, artists need to be quick on their feet. Outdoors, where the light and shadows are in constant motion, it’s important to be able to mix a color intuitively. Just like having all your painting gear in order so you are not wasting motion in the field, a thorough knowledge of color is necessary to be able to concentrate on the important issues of your subject.

There are two main points when addressing color, for any type of painting:

First, how to mix it. And second, how to get color harmony. The mixing part is easy and is more science than art. There are four components to this: hue, value, intensity and temperature. When each of the four components is correct, the color that you want will be correct also.

Each year in my college classes, I usually run the group through a series of color-mixing exercises. To do this, I pass out color swatches from the paint store and ask them to make a match, as close as possible. Usually they are required to mix a grayed-down version of one of the primaries or secondaries, because coming up with a match for a saturated color would be too easy.

Color Mixing for Plein Air Painters
John Hughes’ palette

Let’s face it, it’s those grays that give many artists the most trouble. It’s easy to spot a primary or secondary color, but the ones that are less obvious are the ones that can throw you. Sometimes, if a color is grayed down a lot, it’s almost impossible for a novice to figure out how to mix it. The reason for this is that when a color is almost completely neutral, it lacks any trace of a primary or secondary starting point (more on this in a minute).

Well, if you are finding yourself in this situation, I hope that what I am about to share will take some of the mystery out of color mixing for you. Let’s start at the beginning: Your first job is to pick the general hue of the color you want. That’s usually the first step; the order of the last three steps can vary.

Let me just say that I approach color in terms of primary triads. Whatever the color to be mixed, a triad is the simplest method to arrive at what I want. And before going any further, let me share my choice of palette: I am presently using a sort of warm/cool primary palette, with a twist. These are all Utrecht colors, mainly because I have a Blick/Utrecht store only a few miles away from my studio. Utrecht is a good brand, but so are a lot of others, so go with what you are used to.

My colors consist of: cerulean blue hue, ultramarine blue, quinacridone rose, cadmium orange, cadmium lemon yellow, and cadmium yellow medium. That’s it, six colors plus titanium white! I could have gone with a cadmium red light instead of the orange, but this works for me and I can make that color very easily if I need to.

Color Mixing for Plein Air Painters
John Hughes, “Autumn on the Sleeping Indian,” oil — example of graying down colors

As a color-mixing example: If the color that you want to mix is in the red family, just put some red out there. Which red? For me, that’s easy, because I only have one. You can usually get there with any red, though, if you know what you are doing. But let’s just say that if the color you want is cool, put a cool red out, or if it’s warm, choose your warm red. Don’t stress too much over this — color mixing is very forgiving in many ways.

Now that you have the hue problem solved, value is a good next step. I say that because, as I mentioned, there is no set order for using these last three components of color. You could go for intensity or temperature next, but for me, value is an easier choice.

Next question: Is the red you want darker or lighter than the red you put on the palette? If darker, you can adjust the red with a darker color from your palette. With my palette, the choice is going to be ultramarine blue and a touch of cadmium orange or one of my yellows, to keep the red from crossing into the violet range. The same thing could be accomplished with an earth color, like raw or burnt umber.

Color Mixing for Plein Air Painters
John Hughes, “Wanship Barn,” oil — example of harmonizing more saturated colors

If the color you are after is lighter than the red you put out there, you can choose a lighter color from your palette, or white. The white will also cool the resulting mixture and may be too chalky for a foreground color, so with my palette, I might choose one of my yellows to lighten it. If the yellow brings the red too far toward the orange, a touch of blue and maybe even a slight addition of white will usually work to straighten out the problem.

Now that you have the hue and value figured out, the only thing left is intensity and temperature. To knock down the intensity, just add enough green (yellow and blue on my palette), because it’s the complement of red, to get it to where you want it. From there all you need to know is whether the color is warmer or cooler than the one you have so far.

If the color you want is warmer, you can add yellow, or orange. If it’s cooler, just add some blue, or another cool color on your palette. Just make sure that this color will do the job and not change the basic hue again! You can also add a bit of white if it will work on the area of the painting that you are addressing.

Voila, you have your color! This may sound complicated, but after a while it will seem natural, just like riding a bike.

As you can see, changing one property of a color isn’t so cut and dried! When you make a change in one aspect, like the value, you might also be changing the hue, temperature, or intensity at the same time. Controlling these can be a bit frustrating — in the beginning it may seem like juggling bowling pins! Therefore, practice is key, and I suggest that the reader work with color swatches for a while, as well as going into the field and just matching colors that you see in nature. This will do more to advance your color knowledge than attempting a full-blown painting the first time out. It’s even a good skill-sharpener for artists who have already spent time in the field.

Tree greens, at first, give students the most problems. Typically, a beginner who wants to paint a pine tree slaps some viridian green on the canvas, straight out of the tube! It’s an understandable mistake, based on the idea that trees are green, at least in our minds! We all did this in elementary school, right? When it came time to draw the tree in art period, didn’t we all pull out that blasted green crayon? As adult painters, though, we need more perception based on observation to mix our colors. Viridian might work as a starting point for those pines, but the addition of a red or an earth tone is going to temper that green in a way that more closely mimics nature. Remember, observation is always the arbiter of judgment and execution in painting!

Color Mixing for Plein Air Painters
Hughes in the field

One Last Note on Mixing Colors

If you find that the color is almost devoid of a starting hue, as mentioned previously, know this: You are dealing with a combination of all three primaries (red, yellow and blue). In that case, just mix up a gray using these colors to start, and then tip the mixture toward any primary or secondary that you desire. This is the “backward method” of the process I identified above, but certainly not backward as an approach! This is one way to think outside the box when mixing color, and a very effective way at that!

So why do I use only six colors? The answer is, it’s a limited palette and it gives me good color harmony. You see, no matter what color system you use, the common denominator is fewer colors equals more harmony and more colors equals more chances for discord. Having said that, some artists love large palettes with lots of exotic colors, and that’s OK — they just must do other things to bring those varied colors into harmony with each other.

More than likely, they will be employing a mother color to rein in the palette. (A mother color is basically just a common tone that is put into all the colors, or into all the mixtures, to achieve harmony). It all goes back to the principle of common tones, which tend to harmonize every color on the palette. Whichever approach to color harmony you prefer — complementary, split complementary, analogous, mother color, or a limited palette — when fully evaluated, the underlying principle always goes back to again, to common tones. Now, doesn’t that take some of the mystery out of all those systems?

One last note on study: Always ask yourself what the operative principle of a so called “rule” is. You can save a lot of time and energy by approaching your learning this way, instead of memorizing a lot of seemingly unrelated information.

Color Theory Tips for Plein Air Artists:

Below I have included a little chart that shows how this all works:

Mixing Color

1) Hue = (6 Choices—Red, Yellow, Blue, Green, Orange, Violet)

2) Value = (1 – 2 – 3 – 4 – 5 – 6 – 7 – 8 – 9)

3) Intensity = (Example: From red to Green)

(Intense Red) – (Medium Intensity Red) – (Low Intensity Red) – (Neutral) – (Low Intensity Green) – (Medium Intensity Green) – (Intense Green)

4) Temperature = Warm or Cool

Example: Red violet and blue violet are both temperatures of violet. Red violet is warm and blue violet is cool.

5) Harmony = Common Tones

Common color harmony devices: Complementary, split complementary, analogous, mother color, limited palette.

John Hughes is a plein air and studio artist with over 35 years experience. He teaches workshops and classes through the Scottsdale Artist’s School, as well as Salt Lake Community College and other venues. He has written numerous articles on painting for Fibonacci Fine Arts Digest, 15 Bytes and OutdoorPainter. His galleries include Mountain Trails Gallery in Jackson Hole, Wyoming, and Montgomery Lee Fine Art in Park City, Utah. John is a member of the Rocky Mountain Plein Air Painters, Plein Air Painters of Utah, and the American Impressionist Society.

To view John’s work and find out about his future workshops, visit his website at

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  1. I really enjoyed this article and learned about harmonizing the colors. It’s time to get color swatches and match them!! Very well explained principle.

  2. Thanks so much for all your help! I wish I could get my hands on your entire collection of articles, as I save them, then lose them.
    Just signed up, so maybe I can collect them all.
    Best wishes to you for your continuing painting and writing adventures!
    Dot Holladay

  3. Thank you judi and Dot, Really glad to hear that you are getting something good out of these articles! Hope you can join my newsletter if you haven’t already. Thanks so much ! John-

  4. Thank you John for another thought provoking article. I learn so much from your detailed but clear descriptions of color mixing and harmony. This article should be a must read, reread, and practice for every student of art

  5. I loved your article John. I am a fan of your artwork and really enjoyed the backward process of mixing the grays and then adding the primary or secondary color. I am saving these notes.

  6. I have read so many books on colour theory and colour mixing. But no one has explained the points as simply and clearly as you have done. You have cleared many doubts and confusions which have been challenging me for many years. Thank you very much.


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