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Instead of a direct reply to your inquiry, let me just say that I have shot flowers with 15mm FE, 800L and most Canon lenses in between. Each lens opens up a rather unique view and perhaps an opportunity for something out of ordinary once in a while.
Bingo. I think our prodigious bird dude is right. Depends on vision and mood. Only thing I add, looking at your trial paperwhite, is get a collapsible translucent diffusion panel to shade the scene. That way white petals can retain all their detail without the wide variation in exposure from background or leaves. Or shade them somehow to reduce exposure difference on the white versus other parts of scene.
I do not keep many photos on line, but these few vary from like 60mm to 420mm, and I have shot flowers down to 13-15mm. All focal lengths good, depending on flower size. Wide angle is excellent for "thing in their environment field close-ups."