Oops! Not just the petals, then. What we have here, when we read the lines as a whole sentence, is the beginning of a list – "we could see nothing but A and B." So now we're adding to the things that are taking up all of our attention.
So the petals were hair. What's the eye? Probably the middle of the flower – think the middle of a daisy. In poppies, this center is very large, usually dark purple or black, hence the "sooty," and a little fuzzy, hence the "lashes." (Check out this close-up of the center of a poppy.)
But what about that "lewd, bold" part? This is a little risqué – the word lewd means, literally, "obscene or indecent." And we're not talking about swear words, here.
So not only does the poppy now have big, trademark hair, but a bold, unblinking eye. That might be a little…direct, no? A little suggestive, maybe? It's as if the poppy, during its brief and raucous life, has a constant "come-hither" stare. Ooh la la.