The Duffer’s Guide to Painting Watercolour Landscapes. Don Harrison

neutral or dull they become because the colours ‘lean’ in the wrong direction.

      Mixing just two primaries together is slightly limiting and may not produce the subtle hue you need, so what about mixing three together to produce neutral tints? This seems to contradict the advice I have just given you: it is true that mixing equal amounts of the three primary colours produces a very dull grey or muddy mixture. The important point is to add just a tiny amount of the third primary to produce a neutral hue. To tone down a single primary, just add tiny amounts of the other two primaries.

      The beauty of arranging your colours on a round palette to match the colour wheel is that complementary colours, whether mixtures or individual colours, are always roughly opposite each other, so you know where they are without having to think about it.