The convergence of flowers with varying floral organs into a recognizable shape despite their different meristic composition suggests some benefit of this shape. This benefit may be as simple as having a generally recognizable ‘flower shape’ to pollinators, though the floral bauplan is surely shaped by many biotic and abiotic agents of selection, as well as investment costs. Here, we propose a very simple geometric model of a simple actinomorphic flower and a more complicated ‘flower’ (i.e. an aster inflorescence). Using very few assumptions about investment in tissues and pollinator attraction, we make some basic predictions of floral form, which quantitatively matches several groups of plants well, though others quite poorly. We discuss the implications of its good match to certain groups and poor match to others in light of the evolution of floral shape.