how does one set grass clump population to have a green colour?...
i have assigned a surface shader which is green to the grass clump but still when i preview . the grass is still grey..
Assigning a surface layer ought to work, but by default it already has a Default Shader assigned, which can easily be used to change color. Click on the grass clump inside your populator, go to the Surface Shaders tab, click the ... button next to the Surface Shader input field and click Go to "Default shader 01". This will bring up the Default Shader settings. Now just change the Diffuse Color and you should be set. You can use more complex shaders in place of the Default Shader to get different effects.
Great that worked!!...