South Dakota Native Plant Research
Acorus americanus

Scientific Name

Acorus americanus


Download Seed: Sweet flag produces few seeds (54 KB)

Download Seedling: Seedling picture (116 KB)

Download Leaves (207 KB)

Download Rhizome (394 KB)

Download spathe and spadex (137 KB)

Family Name


Common Name

Sweet flag

Native American Name

Dakota: sinkpe-ta-wote; Lakota: sunka ce


Acorus americanus is a grass-like perennial forb, which grows 3ft to 5ft in height. This species is commonly found in swamps and marshes. The plant is strongly rhizomatous. The leaves are ensiform, erect and linear. Acorus calamus has a space that is 4-9 cm long with light brown greenish-brown perfect flowers that are enclosed by a leaf-like spathe. Flowering occurs from May to July. The perianth has 6 short segments, there are 6 stamens, and the pistil contains 2-3 locules. The fruit is a small capsule containing 2-3 seeds. The rhizomes are quite fragrant and are used both as medicines and food by several of the Northern Great Plains tribal peoples.

Additional Notes

The Dakota name ""sinkpe-ta-wote"", means muskrat food.

Horticulture Notes

Seed Collection: Late summer, before seeds are shed.
Germination: Stratification over winter in moist soil.
Vegetative Propagation: By division of the rhizomes
Soils: Wet fertile soil
Light: Full sun
Water: Thrives in wet areas
Notes: The roots grow in a broad array just below the surface of the soil

Acorus americanus