How to Mix Clean Colors (and Avoid Mud): A Watercolor Artist’s Guide

Mixing colors is one of the most satisfying parts of watercolor painting — but it’s also one of the easiest ways to end up with dull, lifeless mud if you’re not careful.

As a visual artist who works with watercolor and mixed media, I’ve seen how a thoughtful approach to color mixing can take a painting from flat to luminous. Here's how to keep your mixes fresh, clean, and vibrant — and how to avoid that dreaded muddy mess.

What Causes Mud in Watercolor?

“Mud” happens when too many pigments are combined, especially when they’re not color-friendly. Watercolor is transparent by nature, so everything you mix and layer shows through. If you overdo it with heavy, opaque, or opposing colors, they can cancel each other out and turn murky.

Common culprits:

• Overmixing too many colors at once

• Mixing complementary colors (red + green, blue + orange, yellow + purple) without intention

• Using low-quality or overly granulating pigments

• Working wet-on-wet without planning

7 Tips to Mix Clean, Vibrant Colors

1. Know Your Color Wheel

The color wheel is your best friend when mixing. Colors opposite each other (complementary colors) neutralize one another, which can lead to muted or muddy results if not used intentionally.

• Want vibrant greens? Mix a cool yellow (like Hansa Yellow Light) with a cool blue (like Phthalo Blue).

• Want rich purples? Pair a cool red (like Quinacridone Rose) with a cool blue (like Cobalt Blue or Ultramarine).

Warm + warm or cool + cool generally = cleaner, brighter mixes.

2. Limit Your Palette When Mixing

Stick to mixing two pigments at a time when possible. The more colors you add, the more likely you are to create mud.

Try this exercise: Mix two primary colors to make a secondary (e.g., yellow + blue = green), then add small amounts of a third color only if needed. Keep it simple.

3. Learn Your Pigments

Not all paints are created equal. Each tube or pan contains a specific pigment, identified by a pigment code (like PB29 for Ultramarine Blue). Some pigments are cleaner mixers than others.

Choose single-pigment paints when you want bright, clean mixes. Multi-pigment colors can be beautiful, but they’re more unpredictable when mixed.

4. Use a Clean Palette and Brush

It seems obvious, but a dirty brush or palette full of leftovers can muddy your mixes fast. Rinse your brush thoroughly between colors and wipe your mixing area clean.

5. Mix Next to Each Other, Not On Top of Each Other

When layering, let each layer dry fully before adding another. If you apply wet paint on top of wet paint (especially if they’re opposing colors), you risk them blending into brown.

Tip: “Glazing” (layering transparent colors) works best when each wash is bone dry.

6. Swatch and Test Before Applying

Test your color mixes on a scrap piece of watercolor paper before committing. Watercolor can look very different wet vs. dry, so take time to preview how your mix behaves.

7. Embrace Neutrals — On Purpose

Not all muted tones are bad! Purposeful neutrals can add depth and atmosphere to your painting — think misty skies, distant mountains, or natural shadows. The key is mixing them intentionally.

To make a rich neutral:

• Mix Ultramarine Blue + Burnt Sienna

  

• Or Alizarin Crimson + Viridian Green

  

These combos create beautiful grays and browns (and a few things in between!) without looking muddy.

Bonus Tip: Make a Mixing Chart

Create your own color mixing chart using your current palette. This not only helps you avoid guesswork but shows you how your specific paints interact — which combinations sing, and which sink.

Final Thoughts: Mix with Confidence

Avoiding mud in watercolor isn’t about avoiding color — it’s about knowing how colors work together. With a little planning and practice, you can mix vibrant, expressive hues that bring your work to life.

So next time you reach for that brush, think like a color chef: use clean tools, the right ingredients, and just the right touch.

Track your own color mixing experiments with this free printable PDF blank color mixing chart!

Blank 8 color mixing chart.pdf

Download PDF • 2KB