Ilex cassine grows where most ornamentals refuse to go: in standing water, in the dense humid shade of coastal plain forests, in the mucky margins of Carolina bays and tidal swamps. Native to the southeastern United States and the Caribbean, it is a tree calibrated for difficulty, reaching 20 to 30 feet in the wild but settling into a more modest, shrubby form in cultivated gardens. The foliage is notably smooth and un-spined, a quiet contrast to the bristling leaves of American holly, and female plants reward patience with generous clusters of red berries through fall and winter.

In the landscape, Dahoon asks for moisture and some protection from hard winters, particularly when young. It thrives in zones 7 through 11 in full sun or partial shade, preferring acidic soils and resenting root disturbance once established. Plant it into its permanent spot and let it settle in; it will reward that early commitment with years of trouble-free growth. Like all hollies it is dioecious, so a male plant nearby is needed to coax fruiting from females. For native plantings, rain gardens, or the damp edges of a pond, it is a genuinely underused choice.