I actually completed this project in Procreate instead of Photoshop and really enjoyed the process.

Just a tip for the Procreate users: if working on a large canvas, layers quickly become an issue. To work around this, I created various canvas: one as a library for the elements, one for the leaves, one for the flowers. 
And finally made a composition on another one.

This class was great, instructive and fun, with a very cool teacher :)

My watercolors petals, leaves and stems: