This looks phenomenal, your rendering is amazing. My only critiques are I wish you had more areas where the roots actually go over the rocks and I feel like you could add some more noise to the background dirt similar to how you did in your first stone texture.
I agree that the dirt is looking a little flat. I've seen you do some nice subtle dirt renderings before, refer to your old work to see what was/wasn't working to help you grow. For the roots, it might not only be cool to have some growing over the rocks, but you might want to try making them look embedded by making the shadows stronger or adding some buildup around the edges.Don't forget to add some extra flecks of 'sparkle' to spec for the rocks.