Savannah iris is a perennial bulb in the Iridaceae (iris) family native to just 5 states in the southeastern U.S.A. with showy blue-purple flowers. In North Carolina, it grows in shady swamps and wetlands in the coastal plain. The genus name Iris is named after the Greek Goddess of rainbows. The species name tridentata is Latin for "three teeth". The fragrant showy purple flowers appear from May to June. and it can form colonies from spreading rhizomes. This plant is native to boggy soils but will grow in drier conditions. However, if dry for too long it doesn't bloom well. For best performance, give this plant moist to wet conditions in sandy soils in partial sun to light shade. It will also tolerate growing in a container with an inch or so of soil over the bulb. Savannah iris is resistant to browsing by deer. Grow in a water, rain, or bog garden or to frame a riparian area. Insects, Diseases, and Other Plant Problems: No serious problems. Watch for slugs and snails.
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.
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
Sand
Soil drainage
Occasionally Wet
Available space
12 inches-3 feet
NC region
Coastal
Mature size
Height: 1 ft. 0 in. - 1 ft. 8 in. | Width: 1 ft. 0 in. - 3 ft. 0 in.
Canopy layer
4 - Herbaceous (1-3 ft)
Form & Appearance
Leaf color
Green; Red/Burgundy
Leaf type
Sheath; Simple
Leaf arrangement
Rosulate
Leaf shape
Lanceolate
Leaf margin
Entire
Leaf size
> 6 inches long, 1-3 inches wide
Hairs present
No
Leaf detail
Strap-like leaves are bright green, 12-18 inches long and .5 to 1.5 inches wide, basal and upright. Margins are entire and occasionally tinged with red-brown. They encircle the stem.
Flower color
Blue; Purple/Lavender
Flower value
Fragrant; Showy
Flower size
1-3 inches
Flower detail
Fragrant blue-purple wide sepals spread and then arch down. They have dark purple veins and a white to yellow signals. Petals are much smaller only 1-2 cm in threes and resemble teeth. Blooms appear singly from May to June on 2-foot green stalks that rise above the leaves.
Bloom time
Summer
Fruit type
Capsule
Fruit detail
Round to oblong seed capsule August to October
Stem color
Green
Stem detail
Green round stem up to 2 feet tall sometime branched but usualy holding only one flower.
Wildlife & Ecology
Native status
Native
Origin
Southeastern U.S.A. from southeastern NC to northern FL
Distribution
NC, SC, GA, FL, TN
Wildlife value
Attracts hummingbirds, butterflies, and mammals.
Attracts
Butterflies; Hummingbirds; Small Mammals
Food & Medicine
Harvest time
Fall
Fruit type
Capsule
Landscape Use
Landscape location
Coastal; Container; Pond; Riparian
Landscape theme
Butterfly Garden; Native Garden; Rain Garden; Water Garden