Swamp Rose Mallow, belonging to the mallow family (Malvacea) and is an herbaceous, shrub-like, perennial wetland plant noted for its showy flowers. It is endemic to the southeast U.S. in areas wet with fresh or brackish water such as swamps, marshes, ditches, and edges of ponds and rivers. It grows to a height of up to ten to fifteen feet and thrives in warm temperatures that promote bud and flower growth. Plants die back to the ground each winter. Growth sprouts again in spring and the flowers and more stalks emerge with each year's new growth. Propagation is by seed and stem cuttings. Its fragrant flowers span up to ten inches wide and are one of the largest in North America. Blooms open at night, are very attractive in the moonlight, last for a day, and are replenished with ongoing blooms. Use this plant in full to partial sun in moist to wet soils with high organic matter around ponds, streams, swamps or bogs. It can also be used in a container. Insects, Diseases, and Other Plant Problems: Watch whiteflies, mealybugs, spider mites, and caterpillars. Potential diseases are leaf spots, powdery mildew, rust, Botrytis blight, and root rot.
Curated pairwise relationships between this plant and others in the library — who feeds
whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.
No curated interactions recorded for this species yet.
Also noted by NC State
Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell
apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.
Herbaceous Perennial; Perennial; Water Plant; Wildflower
Life cycle
Perennial
USDA zones
8a, 8b, 9a, 9b, 10a, 10b, 11a, 11b
Light
Full sun (6 or more hours of direct sunlight a day) | Partial Shade (Direct sunlight only part of the day, 2-6 hours)
Soil texture
High Organic Matter; Loam (Silt); Sand
Soil pH
Acid (<6.0); Neutral (6.0-8.0)
Soil drainage
Frequent Standing Water | Occasional Flooding | Occasionally Wet
Available space
3 feet-6 feet
NC region
Coastal
Mature size
Height: 6 ft. 0 in. - 15 ft. 0 in. | Width: 2 ft. 0 in. - 4 ft. 0 in.
Growth rate
Medium
Maintenance
Medium
Canopy layer
2 - Understory (15-40 ft)
Form & Appearance
Habit / form
Erect
Texture
Medium
Leaf color
Green
Leaf type
Simple
Leaf arrangement
Alternate
Leaf shape
Cordate; Deltoid
Leaf margin
Lobed; Serrate
Leaf feel
Velvety
Leaf size
> 6 inches long, > 6 inches wide
Hairs present
Yes
Leaf detail
Velvety alternate, heart-shaped, leaves are grayish-green and have 3 to 5 shallow lobes with a toothed margin. Leaves are fuzzy on the top and underside and up to 10 inches long and wide.
Flower color
Pink; White
Flower value
Long Bloom Season; Showy
Flower form
Solitary
Flower shape
Funnel
Flower size
> 6 inches
Flower detail
Showy pink or white fragrant flowers have 5 overlapping petals with an attractively contrasting reddish-purple center with multiple yellow stamens. The 6-10 inch flowers occur singly on a leaf axil. Blooms open at night and last for only a day or two but are replenished constantly with many blooms throughout the bloom season that extends from late spring through late summer.
Bloom time
Spring; Summer
Fruit color
Brown/Copper
Fruit type
Capsule
Fruit detail
Pubescent capsule surrounded by the remnants of the calyx
Stem color
Green; Red/Burgundy
Stem detail
Green or reddish stems with star-shaped hairs
Wildlife & Ecology
Native status
Unknown
Origin
SE USA
Distribution
AL, FL, GA, LA, MS, TX
Wildlife value
Flowers attract hummingbirds and butterflies. Seed pods provide birds with a food source.