Acorus calamus

Sweet flag is a non-flowering, aquatic perennial, rush or sedge in the acorus family, native to Central Asia. Basal leaves emerge directly from a spreading rootstock, erect and sword-shaped, 3/4 of an inch wide and typically growing up to 30 inches tall. Leaves and rhizomes are sweetly scented when crushed, hence the common name. The genus name comes from the Greek for pupil, because the plant was used to treat inflammation of the eye. The species name refers to the plant's reed-like appearance.

Easily grown in boggy, medium to wet soils in full sun or partial shade, Sweet flag appreciates afternoon shade, especially in hot southern summers.  It will grow well in shallow standing water up to 9 inches deep as well as in consistently moist garden soil.

It is grown primarily as an accent or specimen foliage plant in pond or water gardens, but it can be found in low spots, naturalized, or woodland areas as long as high soil moisture is maintained. To grow in a water gardens, plant rhizomes slightly below the soil surface in moist soils at the water’s edge or in containers set in shallow water. You can also plant rhizomes or existing clumps in containers sunk into wet boggy areas, which will prevent invasive spread. This plant does slowly naturalize by creeping rhizomes and can form large colonies in the wild.

Insects, Diseases, and Other Plant Problems: 

No serious problems.  Leaf scorch can occur if soils are not kept consistently moist.