Leaves: petiole 6-26 mm. Leaf blade dark olive-green, elliptic to lanceolate, 5-21 × 1.5-6 cm, base cuneate, apex acute to acuminate. Flowers 2.5-5 cm diam.; peduncle 1-11 cm; bracteoles 3-6; tepals 21-33, red-maroon, rarely white or pink, inner tepals ligulate; stamens 25-50; pistils 11-21. Fruit aggregates collectively 2.5-4 cm diam., usually with 10-15 pistils at maturity. Seeds pale brown. 2 n = 26.

Flowering midspring-early summer. Along streams, in marshy areas, moist woods; 0-500 m; Ala., Fla., Ga., La., Miss.; ne Mexico.

Illicium floridanum was placed in Illicium sect. Badiana by A. C. Smith (1947). The flowers of the species are pollinated by a variety of insects; fruit set is low (L. B. Thien et al. 1983). The seeds are dispersed by explosive dehiscence of the follicles (M. L. Roberts and R. R. Haynes 1983).

This species is cultivated in southeastern United States (M. A. Dirr 1986) and elsewhere. Illicium mexicanum A. C. Smith was considered a separate species by A. C. Smith (1947); expressions of all characters used to differentiate the two species overlap, however, and it seems best to consider them conspecific.