[6][7] The large flowers come in a range of shades from red-purple,[4][6][8] to bright red[2] to brown,[6] and occasionally yellow.

[6] The iris flowers have three pollination units, each of which is composed of a sepal and stylar branch subtended by a single anther and the nectary.

[15] Iris nelsonii was then first published and described by Randolph in 'Baileya' (a Quarterly Journal of Horticultural Taxonomy of Ithaca, New York) 14: 150 in 1966.

[4][16][19] It lives in a privately owned Cypress-tupelo gum swamp,[8] with forested edges[2] and fluctuating water levels.

Most iris nelsonii colonies are in ditches and spread along the banks of waterways, although some are still in the centre parts of the swamp.

[8] Due to its very limited native range of a single swamp in 'Vermilion Parish', which is privately owned.

It has been introduced to Palmetto Island State Park to make it viewable to the public and to create a protected habitat.

[22] In 1966, when Randolph when describing the Iris, had mentioned that he had thought it had a hybrid origin, due to various chromosomal and morphological characteristics.

[21] In 1993, Michael L. Arnold (Department of Genetics of University of Georgia), carried out molecular study (using isozyme, cpDNA and RAPD (Random Amplified Polymorphic DNA) markers) on Iris nelsonii.

They need full sunlight, moist, acidic soils (ph of 6.5) with a high organic and fertility content.

For best flowering, moisture is essential during late autumn, winter and spring times, when the plant starts to grow.

The ground must be prepared pre-planting, with the addition of a generous amount of organic matter and the soils dug to about 6inches deep (to allow for new root growth).

This research found that the iris was most commonly visited by Archilochus colubris (ruby-throated hummingbird), then other pollinators include butterflies, wasps, and bee species.

[11] It was found that hummingbirds did not show an initial preference for either flower when they entered multi-species arrays.