Vegetation help

Digital oil painting in Sketchbook Pro. How can I improve the look of my vegetation? Are there certain techniques? Just something more than color variation.

https://preview.redd.it/zxq75j4y8ooe1.png?width=2000&format=png&auto=webp&s=bc59e8696fa5a58a9013c7ef1c5dbf6d9e2f9d8e