If you can imagine it, you can draw it. Took me many years to realize this fundamental fact about drawing. Much of the work of becoming an artist is caught up in learning how to “imagine it,” — in even recognizing what “imagining it” means.
I was looking at these flowers when I drew them, but the whole act of looking involves an imaginative gesture too. The image of “what you think you see” as it organizes itself in your mind.