Turbulence in aquatic vegetation is complicated by the presence of multiple length scales including stem diameter, frontal area per unit volume (an inverse length scale), water depth, and the vertical scale(s) over which stem diameter and frontal area density may vary. While recent experiments demonstrate that turbulent kinetic energy scales strongly with stem diameter in emergent vegetation, and while there is general agreement that turbulence generated in the wakes of plant stems contributes significantly to the turbulent kinetic energy budget even within submerged aquatic canopies, existing Reynolds-Averaged Navier–Stokes models do not account for scaling of turbulence with the stem diameter. We propose a model that addresses this problem by separately treating large and small-scale turbulent kinetic energy.