Living on the edge: How traits of ecosystem engineers drive bio-physical interactions at coastal wetland edges

•Rigid vegetation patches effectively buffer hydrodynamic energy and increase erosion at their edges.•Flexible vegetation patches accumulate sediment closer to their leading edges compared to rigid vegetation for all hydrodynamic conditions tested.•Negative feedbacks may compromise the lateral extension of both types of vegetation.•Lower shoot density causes sediment accumulation to occur further inside vegetation patches.