We study the geometry of phyllotaxis from the viewpoint of circle packing and Vonoroi tiling. Topics of interest include parastichy transition, the limit shape of the Voronoi regions, and the duality of the bifurcation diagrams of Voronoi tilings and circle packings for spiral lattices. We also study the bifurcation loci of distance function on complex foliations, and the complex dynamics around indeterminacy points.