Acorus (uh-KOR-us) Common Name:  Sweet flag grass Light:  - Full sun to part shade Soil:  Humus-rich, moist Moisture:  Consistently moist to constantly wet Blooms:  Insignificant summer blooms Zones:  4 - 8, but varies by species -*-

Acorus calamus 'Variegatus' Acorus gramineus 'Oborozuki'

Acorus Description and Cultural Information

Acorus calamus, sweet flag grass. 24 - 36". Acorus is a waterside rush with long, narrow, iris-like foliage. 'Variegatus' is variegated with cream stripes. The rhizomes are sweetly scented as are the leaves when crushed. Plants spread just below the surface but are not invasive and are easily moved if necessary. Insignificant little white flowers appear in summer, looking like little cattails. Zones 4 - 8.

Acorus gramineus, sweet flag grass. 8 - 12". This Acorus forms a small mound of fine foliage and is useful in a damp and boggy location. 'Oborozuki' is a yellow variegated cultivar and 'Ogon' is a solid yellow plant. They do not appear to be as hardy as A. calamus, generally growing best in zones 6 to 8.

How to grow:  Plant sweet flag grass in full to part shade in average to rich soil at stream and pond edges, or in damp and boggy ground and will even tolerate being slightly under water. However, they do surprisingly well in the moist, well-drained perennial garden and simply tend to grow slightly shorter than their potential. The sweet scented rhizomes, which look very similar to Louisiana iris, should be planted horizontally just below soil level. Division is best done in spring to give the rhizomes time to establish before winter as frost heaving can be a concern in very cold zones.

Landscape uses:  Use Acorus as a marginal plant along streams, ponds, lakes or in tubs. Combine it with other water loving plants such as Rodgersia, yellow flag iris (Iris pseudacorus), Iris versicolor, Lobelia, and cattails. At the same time it also does well in almost any location with good soil and occasional moisture so use it as a vertical accent in the perennial garden.