This image has no white at all. Even the lightest light is a middle value. In order to display those subtle clouds the camera phone sacrifices the large ares of dark. They look pretty much like solid black. That's a lot of nothing happening.
What can you do to enliven those patches of flat black?
The profiles of the landscape elements suggest what you might hint at. It isn't necessary to make careful rendering of trees or rocks. They are already present. Just a little bit of variation in the black should be enough to encourage the viewer to meet you halfway. Try lifting some of the dark, or let the smaller darks within the large shapes have soft edges. The idea is to do as little as possible
Below are a few images that devote too much space to nondescript dark.Try adding or removing a few strokes that will give the viewer something to grasp.
Considering how close to the front of the space it is, that dark shape in the right foreground needs a little something to suggest some texture, but just a little. It doesn't really look bad in the photo, but in a painting it would be a black hole.
There's plenty of recognizable context to identify what comprises the shape. Any marks you make there would be understood to be foliage. See how few touches of the brush the shapes in the middle distance needed. Don't go crazy and start painting every leaf.