This is a nice idea - the interplay of the positive space (the stem) with the negative space (the shadow of the petals). I wonder if the petals could have been lit to make them disappear, so that only the shadow gave them away... Could the stamen have been included in the shot?
Anyway, nice picture, that doesn't do one corner to the other as the diagonal.
I like the visual poetry here, how the flower exists in its own shadow, but I'm not crazy about the composition. It's too static because the subject is centered and there's so much space around it. 6