How do I mix paint colours without getting mud?
Why complementaries cancel, mixing with two colours rather than four, and using a limited palette to keep everything harmonious.
- Difficulty
- beginner
- Time
- 30 min
- Read
- 3 min
Short answer
Mud is what you get when you mix colours from opposite sides of the colour wheel, because they cancel each other. Mix from no more than two or three colours at a time, and start with a limited palette of six so everything you mix is related.
Mud is not a mistake in technique so much as a predictable consequence of the colour wheel. Understanding which pairs cancel makes it both avoidable and, when you want grey or brown, useful.
What you'll need
- A warm and cool version of each primary
- A white palette or plate
- Scrap paper for testing
Step by step
- Learn the wheel.Red, yellow and blue evenly spaced, with orange, green and violet between them. Neighbours mix cleanly; opposites cancel each other into grey or brown.
- Understand what mud actually is.Mixing complementary colours — red with green, blue with orange, yellow with violet — cancels the saturation of both. Since most palettes contain colours from all round the wheel, adding a fourth or fifth colour almost always drags a mix towards its complement.
- Mix with two colours where you can, three at most.Almost every clean mix uses two. Once you are on your fourth colour you are usually correcting a mistake and heading towards grey.
- Use a limited palette.A warm and a cool version of each primary — six tubes. Everything mixed from a small set is automatically harmonious, which is why limited palettes look coherent.
- Know your warm and cool primaries.A blue leaning towards green mixes bright greens; a blue leaning towards violet does not. Picking the wrong one of a pair is the usual reason a mix is dull rather than muddy.
- Add the dark colour to the light one.A tiny amount of dark shifts a light mix a long way; the reverse needs a lot of paint. Always work from light towards dark.
- Test before committing.A dab on scrap paper of the same surface. Watercolour dries lighter, acrylic dries slightly darker, and both look different against white than on the palette.
- Use complementaries deliberately for shadows.A touch of a colour's complement knocks it back without dulling it into grey, which is a far better shadow than adding black.
- Avoid black for darkening.Black flattens and greys a colour. Darken with a deeper related colour or a touch of the complement, which keeps the mix alive.
- Mix more than you need.Rematching an exact mix is difficult and often impossible. Mix generously and keep the leftovers for shadows.
- Keep a mixing chart.A grid of every colour mixed with every other, made once. It takes an afternoon and answers hundreds of future questions.
Tips
- Two colours make a clean mix. Four make mud.
- Add dark into light, never the other way round.
- Darken with a complement or a related dark colour, not black.
Common mistakes
- Adding more colours to correct a mix — Each addition drags the mix towards the centre of the colour wheel, which is grey. The fix for a wrong mix is a fresh mix, not another ingredient.
- Using black to darken everything — Black desaturates as well as darkens, so colours become flat and lifeless. A deeper related colour or the complement darkens while keeping the mix chromatic.
If it doesn't work
Every mix goes grey-brown
Cause: Too many colours, or complementaries combined — Fix: Start fresh with two colours from the same side of the wheel.
Greens look dull and olive
Cause: Warm violet-leaning blue mixed with a warm yellow — Fix: Use a green-leaning blue with a cool yellow for bright greens.
Colours look dead when dry
Cause: Black used to darken, or over-mixing — Fix: Darken with complements, and stop stirring once the colour is made.
Cannot rematch a mix
Cause: Mixed too little — Fix: Always mix more than needed, and note the proportions on a chart.
Questions people ask
Why do I need two of each primary?
No real pigment is a pure primary — each leans towards one neighbour. A warm and a cool version of each gives you a clean route to every secondary, which three tubes alone cannot.
Is brown a useful mix or a failure?
Both. Brown is a partially cancelled complementary mix, so it happens by accident constantly, and it is also the correct way to mix natural browns deliberately from colours already on the palette.