First of all I wouldn't, looks like you caught her in the weeds doing something else and looks slightly annoyed about it, her head is bisected from her body by the horizon.
If you must... crank the exposure up until her face is exposed properly let the background go.
You could clean those weeds out of the front of her dark sweater with the clone tool and some patience.
Click between her hands in the dark area, (hopefully will still be black after you increase the exposure? to check your color.
Take a small crop off the top and a smaller crop from the left side.
Take a look at this as a black and white with a vignette, may be a good option.