@mark: i dont know why you dont have that in your list, is it a bad idea? but when i need to do foliage i copy my whole diffuse and blur it and put it as background behind the original. (so instead of a gradient the blurred image)
As far as the best way to make the textures, modeling the grass and rendering it to a plane works pretty well. Check out this thread: http://www.polycount.com/forum/showthread.php?t=79595&highlight=cottage about halfway down the page he breaks down his methos for making his foliage. It gives you a lot of control over how…