Tertiary colors are the six colors you get when you mix a primary color with the secondary color next to it on the color wheel. They are red-orange, yellow-orange, yellow-green, blue-green, blue-purple and red-purple. They fill in the gaps and turn a six-color wheel into the familiar 12-color wheel.
If those words are new, here's the short version. The primary colors are red, yellow and blue. The secondary colors are orange, green and purple. Tertiary colors come third: they sit between a primary and a secondary.
| Tertiary color | Mix | What it looks like |
|---|
| Red-orange | Red + orange | Like a ripe tomato or a bright sunset |
| Yellow-orange | Yellow + orange | Like amber, honey or a marigold |
| Yellow-green | Yellow + green | Like new spring leaves or a lime |
| Blue-green | Blue + green | Like deep water, between blue and teal |
| Blue-purple | Blue + purple | Like a violet flower or a twilight sky |
| Red-purple | Red + purple | Like a raspberry or a dark pink |
Some people use different names for the same colors. Blue-purple is often called blue-violet or violet, red-purple is often called red-violet or magenta, and you'll see names like vermilion for red-orange, amber for yellow-orange and chartreuse for yellow-green. The color names depend on the book, the paint set and the teacher, so don't worry if you see a different label.
The rule is simple: the primary color comes first, then the secondary. That's why it's yellow-green, not green-yellow. The first word is the stronger color. Yellow-green is mostly yellow with some green. Green-yellow isn't used, because green is already made from yellow.
There are two easy ways to think about it, and they come out the same.
Way 1: primary plus secondary. Mix about equal parts of the primary and the secondary next to it. Red plus orange makes red-orange.
Way 2: two parts primary, one part other primary. Because a secondary color is half one primary and half another, you can skip it. For red-orange, mix 2 parts red and 1 part yellow. For blue-green, mix 2 parts blue and 1 part yellow.
| Tertiary color | Using only primaries |
|---|
| Red-orange | 2 parts red + 1 part yellow |
| Yellow-orange | 2 parts yellow + 1 part red |
| Yellow-green | 2 parts yellow + 1 part blue |
| Blue-green | 2 parts blue + 1 part yellow |
| Blue-purple | 2 parts blue + 1 part red |
| Red-purple | 2 parts red + 1 part blue |
These ratios are a starting point. Real paints vary, and stronger colors take over fast, so mix a small amount first and adjust. If a mix turns brownish or gray, you've probably let in a third primary by accident. Many reds, for example, contain a little yellow.
Picture the 12-color wheel as a clock face:
- Yellow at the top.
- Moving clockwise: yellow-green, green, blue-green, blue, blue-purple, purple, red-purple, red, red-orange, orange, yellow-orange.
Each primary is spaced four steps from the next. Each secondary sits halfway between two primaries. The tertiary colors fill in the spots next to the primaries. Our color mixing chart shows the same wheel as a table.
Tertiary colors are some of the most natural-looking colors, because real things are rarely a pure primary or secondary. Here are a few examples:
- Yellow-green: young leaves, limes, grass in bright sun.
- Blue-green: the ocean, a peacock's feathers, deep pools. Try them on our shark coloring pages.
- Red-orange: autumn leaves, a campfire, a fox's fur.
- Yellow-orange: a lion's mane, ripe mangoes, honey.
- Blue-purple: twilight, irises, a night sky.
- Red-purple: berries, grape juice, some flower petals.
If you only ever use pure red, pure green and so on, a picture can look flat. Mixing in tertiary colors gives you richer variety without making a mess of your palette.
Three more terms often come up with the wheel:
- Complementary colors are opposites on the wheel, such as red-orange and blue-green. Side by side they look vivid. Mixed they turn into brown or gray.
- Analogous colors are neighbors on the wheel, such as yellow, yellow-green and green. They go together smoothly, which is great for blending.
- Warm and cool colors split the wheel in half. Red-orange and yellow-orange are warm. Blue-green and blue-purple are cool. See warm and cool colors.
- Mix small test patches first. Put a dab of each mix on scrap paper and let it dry. Some paints look different once dry.
- Add the weaker color to the stronger one slowly. Blue and red usually overpower yellow. For yellow-green or yellow-orange, begin with yellow and add the other color a drop at a time.
- Keep a record. Next to each patch, write the recipe, such as "2 blue + 1 yellow." You'll be able to repeat it later.
- Use clean tools. A bit of leftover red on a brush will quietly turn your yellow-green into something muddy.
- Lighten and darken one step at a time. Add white for a tint. For a shade, add a little of the opposite color on the wheel. Red-orange gets darker and richer with a touch of blue-green, for example.
Dry media can't be stirred, but you can layer them. For blue-green, color light blue first and layer green over it. For red-orange, layer red over orange or orange over red, pressing lightly. If your set already includes names like lime, teal or coral, those are premade tertiary colors, and you can layer them with their neighbors to make the in-between steps. Our guide to how to color with colored pencils goes through layering and pressure.
- Print or draw a blank 12-section circle.
- Color the three primaries in their spots: top, and two others spaced evenly.
- Fill in the three secondaries halfway between each pair.
- Mix and color the six tertiary colors in the remaining gaps.
- Label each one. Check the names against the table above.
A mandala coloring page with 12 sections is a nice way to do this, and the repeating pattern makes mistakes easy to spot. You can also pick one tertiary color and make a page using only light and dark versions of it.
