Search the following locations to find the hidden green flowers.

Bloom all flowers before going through the stone wall and it will appear.
Follow the right side of the yellow flower path, starting from the center rock formation and heading around. The flower set on the right will appear. Do not go to them. Instead, move further to the left and you will see three yellow flowers. Follow the path. Touching them will take you to the top of the canyon and unlock them.
Enter the last area with the three formations surrounding the larger center one. Do not follow the blue flowers. Instead, go left around the edge of the canyon. Go past the blue flowers and look towards the mountain, then follow the "path" going up the mountain.