Scarlet Rose Mallow Vibiscus coccineus
Scarlet Rose Mallow is a herbaceous perennial that may grow 6 to 8 feet tall. The leaves are palmately compound with a finely toothed margin. A very large, showy red flower matures in late summer to early fall.
Flowers of red hibiscus are very large and striking, up to 6 in.wide. The large, bold leaves add to the striking effect. It can be used in wet areas, such as beside ponds or in boggy areas. This plant is slightly salt tolerant.
It is a large plant for the rear of the perennial border, mixed border, or courtyard. Also effective when grouped in moist locations along edges of ponds and streams. This plant is susceptible to damage from deer.
Sometimes commonly called swamp hibiscus because it is native to marshes and swamps in Alabama, Georgia, and Florida.
Photo by KENPEI. GFDL,Creative Commons Attribution Share Alike 2.1 Japan License
Sources:https://plants.ces.ncsu.edu/plants, https://www.wildflower.org/plants/result.php?id_plant=caam2, other authoritative resources and personal experience.