Flooding strongly determines the distribution and abundance of wetland plants, such as like the zonation along a wetland shoreline. However, the mechanism of flooding affecting the distribution of wetland plants is not full understand. In this study, an outdoor experiment was conducted to examine the responses of growth and vegetative reproduction of three dominant species (Carex cinerascens, Miscanthus lutarioriparius and Phalaris arundinacea) in Poyang Lake to duration of submergence, with a goal to link their strategies to submergence to their distribution along the elevation of Poyang Lake. The results showed that 1) after 120 days submergence, the survival rate of M. lutarioriparius began to decrease and all the individuals died after 180 days submergence, whereas all C. cinerascens and P. arundinacea could re-grow after 180 days submergence, 2) Submergence significantly reduced the total biomass of C. cinerascens by the end of the experiment, whereas a short duration of submergence did not significantly affect total biomass of P. arundinacea. 3) After removing the submergence, C. cinerascens tended to allocate more biomass to leaves at the beginning of the re-grow phase, whereas P. arundinacea did not change the allocation among the treatments. Our results could help us understand and predict the population and community changes of wetland plants in Poyang Lake in response to the changing hydrological conditions changing caused by climate change or dams construction.