I wanted to share my take on this for any of you who might have this problem. There are many theories about why mud happens, mixing too many colours together, mixing complimentaries, mixing opaques etc, etc.
Well...... I don't agree with any of that!!!!
For me there are two reasons why mud happens in a painting...
1. Adding different colours to the paper and then fiddling with the brush. You need to let the colours mix by themselves on the paper, add the paint and LEAVE alone!!!! The only help you need give it is to move the paper around.
2. Painting over something before the underlayer is completely dry.... an absolute no, no..... have PATIENCE!!!!! I should practice what I preach!!!
Take a look at these ( already featured in my Planets blog but like to get my money's worth out of things!!!!)
An alternative way to add colour to a wet mix is to splatter or throw paint at the paper (Jean Haines does a lot of that and I defy you to find any mud on her paintings!!!) the key is to let the paint and water do the work, not the brush.
This was a painting done using a step by step by Lydie Pieplu from Paint my Photo as inspiration. I've used lots of colours, just threw them on for the bg and made sure that when I went in with the darker layers around the flowers the paint under was completely dry.
Here's a challenge for you all......try and make mud, make the muddies yukkiest mix you can and observe how it happened. Then, try again and mix as I've tried to describe here. If you feel the colours you are using are impossible to mix without mud, post them here and let me have a go to see if I can manage it!!!