Nutations in growing plant shoots as a morphoelastic flutter instability

Growing plant shoots exhibit spontaneous oscillations that Darwin observed, and termed ‘circumnutations’. Recently, they have received renewed attention for the design optimal actuation of bioinspired robotic devices. We discuss a possible interpretation these as Hopf-type bifurcation in growing morphoelastic rod. Using three-dimensional model numerical simulations, we analyse salient features this flutter-like phenomenon (e.g. characteristic period oscillations) their dependence on details (in particular, impact choosing different growth models) finding that, overall, are robust with respect to changes adopted. This article is part theme issue ‘Topics mathematical complex materials’.