Kosteletzkya pentacarpos is a native subshrub of the eastern United States, found along coastal marshes and brackish waterways from New Jersey south to Florida and west to Texas. It was named North Carolina's Wildflower of the Year in 1990, recognition that speaks to both its ecological value and its garden merit. The soft gray-green leaves are angular and slightly fuzzy, and the plant grows 3 to 6 feet tall with a spread of 2 to 4 feet. From midsummer well into fall, it produces a steady succession of clear pink flowers that are immediately recognizable as members of the mallow family, each one about the size of a small hibiscus bloom.

In the garden, its niche is the difficult wet margin: pond edges, rain gardens, drainage ditches, or any consistently moist site where other flowering shrubs would sulk or rot. It handles salt spray well, which makes it useful in coastal gardens where choices narrow quickly. Hummingbirds and butterflies work the flowers consistently through the long bloom season. Though classified as a subshrub, it behaves like a perennial in most gardens, dying back to the base in winter and reshooting reliably in spring.