Plant growth occurs due to cell proliferation in the meristem. We model the case of
apical meristem specific for branch growth and the case of basal meristem specific for
bulbous plants and grass. In the case of apical growth, our model allows us to describe
the variety of plant forms and lifetimes, endogenous rhythms and apical domination. In the
case of basal growth, the spatial structure, which corresponds to the appearance of
leaves, results from dissipative instability of the homogeneous in space solution. We
study nonlinear dynamics and wave propagation of the corresponding reaction-diffusion
systems. Bifurcation of periodic at infinity waves is investigated numerically.