The research objective was to investigate the main factors affecting the ability of patches of the submerged macrophyte Callitriche platycarpa to influence the dispersal of other aquatic plant species, by trapping vegetative fragments. Hence, we tested the role of propagule traits, spatial patch configuration and hydrodynamic forcing on the number of fragments trapped in a flume laboratory experiment. Moreover, we tested the role of submerged vegetation cover and structure on fragment retention through a field release experiment. The data include a 4-week mesocosm monitoring of vegetative fragment buoyancy, and the number of fragments trapped by submerged vegetation in both flume and field releases.