Mixing colors correctly depends on understanding the factors that differentiate one paint from another. We start by learning basic color theory and then progress to understanding how a watercolor paint's "temperature" (whether it's cool or warm) comes into play when it is mixed with other colors.
I discussed the basic idea of how the temperature of a primary color can be used to make vibrant or dull colors in detail on the Color Mixing 101 page. Here, we will go a step further and I'll show you how to make yourself some color wheels to help you understand the physical results of mixing colors by temperature.
This is a basic color theory wheel which you can find in any art supply store. Nice to have, but I'm going to show you how this basic wheel is not all that helpful when you want to mix a vibrant purple for a flower painting. Yes, it shows you (according to color theory) that if you mix red and blue, you will get some hue of purple.
What the basic wheel doesn't tell you is that you must take into account the relative warmth or coolness of the hues chosen and the associated complement color if you want to create that vibrant purple successfully.
For instance, I made the color wheel page at right for myself. With just a glance now, I can quickly see the different colors I can create by choosing paints which are either warm or cool hues, or muted, natural hues or bright, transparent hues.
Study the wheels I made and you'll see that each wheel has a red, blue and yellow hue that are then mixed in various amounts to make the other colors.
But each wheel looks very different from the others. This is because the red, blue and yellow primary mixing colors I chose were either warmer or cooler, more muted or bright, or have a gray or other neutralizing tint added that made them different from the other paints.
You can make yourself these kinds of reference wheels too. Here's how:
Below are two more wheels I made with some new colors I bought.
The new Pyrrol Scarlet red shade is so warm that it is almost orange and as you can see, it made for a more yellowish orange. The new Cerulean Blue Chrome I bought didn't want to mix well with that Quinacridone Rose. I had to keep mixing them on the palette, and it wanted to separate on the paper too. It was kind of a neat effect if you want that, but I'll keep it in mind the next time I'm mixing colors and aiming for a smooth effect on the paper.
This mixing issue has to do with the particle sizes or granularity of the two paints. Blue colors tend to have larger, clumping particles while red paint colors tend to have smaller particles or granules. So another thing to remember about mixing colors: combining watercolor paints with different granulation rates is a challenge. Most of the paint manufacturers have this granulation information on their color charts. Here are three that I can share:
I hope you found this color wheel exercise fun and informative. I think creating these wheels helps you save paint and time, because you don't have to mix and remix paint on your pallet trying to find the right color combination for what you want to achieve.