Inundation level greatly affected plant survivorship, growth, and nutrient allocation. The macrophytes differed substantially in their abilities to adapt to rising inundation level and in their adaptation strategies. N. odorata exhibited a substantial increase in both biomass and nutrient storage under rising inundation and had the largest accumulation of P and nitrogen among the six species studied. Aboveground biomass (A) and belowground biomass (B) allocation varied with species. Species with a lower A/B ratio under shallow inundation (N. odorata, E. cellulosa, and T. domingensis) adapted better to deeper inundation than those with higher A/B ratios (C. jamaicense, R. tracyi, and E. elongata). Adaptation to deeper inundation was achieved either by an increase in aboveground growth (E. cellulosa and T. domingensis) or by a simultaneous increase in both aboveground and belowground growth (N. odorata). Inability to adjust the A/B ratio in response to deeper inundation was characteristic of species that experienced high mortality (R. tracyi and C. jamaicense). The results of this study, which demonstrate differences in inundation tolerance and differences in mechanisms of inundation tolerance among common and diverse wetland macrophytes, will be useful for wetland restoration and management.