The phenomenon of dynamic symmetry in botanical, the so-called philotaxian, systems is investigated. A mathematical model of phylotaxis grounded on Minkovsky's geometry, as well as the original trigonometric apparatus based upon the golden ratio, are developed. Constant values of phylotaxis dynamic symmetry are defined. The principle of dynamic symmetry in architecture, formulated by D. Hambidge, as well as architect Le Corbusier's Modulor proportional system, are described in terms of philotaxis mathematics.