I'm facing a challenge in detecting the leaves in the image. I've tried color based segmentation so far, but the color of the leaves in an image vary due to lighting and are in similar ranges to other parts of the plant. What other methods can I use? I'm pretty new to image processing. Open to machine learning techniques for classification. I'm using OpenCV 3.3.0 
This is an example input image. The closest I've gotten with color is:
