Setting color of meshes

I’m currently working with meshes, but I can not set the color of it for some reason. With the code below the mesh is white no matter which numbers I pass to render.SetColorModulation(). I’ve also tried to set the color when using the material “models/debug/debugwhite”.

[lua]
function ENT:Draw( )

self:DrawModel( )

render.SetColorMaterial()
render.SetColorModulation( 1, 0, 0)

local matrix = Matrix( )
matrix:Translate( self:GetPos( ) )
matrix:Rotate( self:GetAngles( ) )
matrix:Scale( Vector( 1, 1, 1 ) )

cam.PushModelMatrix( matrix )

	mesh.Begin( MATERIAL_QUADS, 6 )
		mesh.Quad( Vector(0,50,0), Vector(50,50,0) , Vector(50,0,0), Vector(0,0,0))
	mesh.End( )

cam.PopModelMatrix( )

end
[/lua]