Easy to underestimate how much time a lot of close up foliage would take to paint out. The safe thing is to finish up all the overall tones and colors first, so if you have to put the painting down, at least you will have a full albeit rough image.

You can find more of my work at:
http://syncup.deviantart.com/ and https://torewesolowskidesign.artstation.com/
にほんごもだいじょうぶです。