This effect will look as if water has run down the wall. Adding some raw umber universal stainer, which gives a green-brown tint, will simulate moss.
Follow instructions for Faux Plaster and use a wide brush. For easy blending and to avoid 'seams' when glazing walls remember to leave a wet border around each section as you work down the wall.
1. After blending the colors, take a dry 50mm (2 in) or 100mm (4 in) brush and, while the paint is still wet, start pushing and brushing it to one side. This will build up an irregular and darker pattern. Cross-brush to ensure there is no streaking. Soften with a wide Japanese hake.
2. Dip your fingers into a container of methylated spirits/denatured alcohol and flick it onto the wet paint. Wait for it to evaporate and then brush it in all directions using a soft, dry brush to create interesting, crater-like marks.
3. Before the paint dries, wipe it with a clean, wet cloth to create a faded effect.
Source: Pictures and excerpts taken from the book Decorative Paint Finishes by Louis Hennigs and Marina Niven. Published by Struik
