Control time transition between colors

Hi,

Please help, I have problems trying to fix this script...

I want to change the color of the material and I want to control the time of transitions between colors.

Now I can change the Color without problems, but now I want to smooth the transition between colors.

Please any advice is more than welcome.

 var fadeSpeed : float = 7.5;
 var NextColors : Color[];
 var NextMaterial : int = 0;
    
   
 function NextMaterialUsed()
 {
     GetComponent.<Renderer>().material.color = Mathf.Lerp(GetComponent.<Renderer>().NextColors[NextMaterial],.material.color,Time.deltaTime * fadeSpeed);          
     if(NextMaterial < NextColors.length-1)
         NextMaterial += 1;
     else
         NextMaterial = 0;
 }