This is a Procedural Moss Material that uses Displacements. A highly subdivided model works best for this material. There are 2 custom node groups. One node group allows you to have a material underneath the moss shader and the other sets the material on the object to only moss. You will need to add your custom shader in the place of the Diffuse shader. There are also 2 other custom nodegroups for the placement of moss on the object, one is a gradient placement and the other is random placement of moss on the object with customizable settings. The custom node group for the moss shader contains:

• Slot to add custom shader which will be shown under the moss
• Moss Placement input that accepts input from the custom Moss Placement nodes
• 2 different customizable colours for the moss
• Subsurface scattering level
• Subsurface colour
• Scale slider to scale the texture
• 2 different sliders to change the bump strengths
• A slider to set the displacement scale.