The interaction between plant growth and nutrient availability is an important aspect of vegetation dynamics in wetlands. In this study, seedlings of Typha domingensis were used to assay the nutrient availability of fire-disturbed Florida Everglades soils. Seedlings were planted in soils that had been naturally muck- (MB), surface- (SB), or non-burned (NB) and that showed significant differences in concentrations of inorganic:total phosphorus according to fire severity. After two months of growth, plant height, number of leaves, culm diameter, number of rhizomes, length of rhizomes, live leaf biomass, and above- and below-ground biomass were greatest in MB seedlings. In addition, root architecture and biomass allocation were influenced by soil type. Seedlings from NB and SB soils developed thinner roots with numerous root hairs and had higher percentages of below-ground biomass. In contrast, seedlings grown in muck-burned soils developed large rhizomes in addition to thicker, hairless roots while allocating proportionally more biomass to aboveground parts. Tissue nutrient analyses showed that both experimental and field-harvested plants grown in MB soils contained significantly more phosphorus than plants from SB or NB soils. Typha domingensis has displaced plant communities in areas of the Everglades that receive nutrient-enriched agricultural runoff. However, this study suggests that establishment and expansion of this species also may occur in overdrained regions of the Everglades where muck fires are a frequent occurrence. In addition to creating an opening in the landscape, muck fires increase the bioavailability of soil phosphorus, thus providing a competitive advantage for T. domingensis.