Dixie iris is very rare plant in the Iridaceae family found in a range of South Carolina to Florida and Louisiana. In the wild is grows in wet, shallow, sunny areas such as marshes, ditches, swamps, and streams or riversides of the coastal areas.
This herbaceous perennial grows to 3-4 feet tall and spreads 1-1.5 feet but the leaves die back after the early spring bloom and reappear in the fall for the next season. It prefers full sun however it can tolerate some shade and moist to wet acidic rich soils. Soils that are on the drier side can be mitigated with a heavy application of wet mulch to keep the soil cool and reduce evaporation.
The blue to lavender flowers are more similar to I. hollandica than I. germanica in that the flowers on tall 1-3 foot stems are delicate and crisp with the three standards being narrower and shorter over the three widespread falls. The seed pod is hexagonal, but the preferred method of propagation is through the division of the rhizomes planted shallowly.
It can grow in several inches of water; so are perfect for that low spot in the landscape that never drains, a bog garden or pond gardens. The rhizomes can spread easily making it good for naturalizing or planting along a border.
Source: https://plants.ces.ncsu.edu/plants/iris-hexagona/