Wetland plants are hydrophytes (hydro = water, phyte = plant). These are plants growing in water or on soil that at least periodically is deficient in oxygen due to excessive water content. Hydrophytes have morphological, physiological and reproductive adaptations that allow them to thrive in inundated or saturated soils where non-hydrophytes (upland plants) cannot. Plant communities dominated by hydrophytes are referred to as hydrophytic plant communities.
In general, wetland plant communities are organized according to water permanence, depth and degree of soil saturation from deepwater wetlands to seasonally flooded basins and potholes. There are 15 wetland plant communities in Minnesota, with more than 370 plant species. Note that upland plants occasionally occur in wetlands and, conversely, wetland plants occasionally occur in upland habitats. This is especially true in transitional areas between wetlands and uplands.