Culture
Easily grown in medium to wet soils in part shade. Foliage color is richer in part shade than in sun. Plants tend to languish in full shade. Plants thrive in moist soils, but also perform well in average garden soils, with better tolerance for periods of dryness than most sedges have. Plants generally dislike hot and humid summer climates. Plants are evergreen throughout most of their growing range. Where not evergreen, foliage should be cut to the ground and removed in late winter. Plants spread slowly by short rhizomes. Propagate by rhizome division.
Noteworthy Characteristics
Carex oshimensis, commonly known as Oshima kan suge, is a fine-textured sedge that typically grows in a low, grass-like mounded clump to 10-16” tall and as wide. It is native to dry woods and rocky slopes throughout Honshu Island, Japan. This sedge features narrow leaves (typically to 16” long by 5/16” wide). Insignificant brownish flower spikes appear on triangular stems in spring. This sedge is evergreen in the deep South, maintaining good foliage in both summer and winter. It is not totally evergreen in the St. Louis area, although some foliage color will persist through mild winters. Plants are similar in appearance to Carex morrowii.
Genus name from Latin means cutter in reference to the sharp leaves and stem edges (rushes are round but sedges have edges) found on most species' plants.
‘Everillo’ is a bright new compact cultivar. Cheery cascading foliage is uniformly yellow in color growing up to 27 inches in height and 18 inches in width. It occurred as a whole-plant mutation of Carex oshimensis ‘Evergold.’ Grown for colorful container and landscape use, primarily in shaded exposures. US PP21,002 awarded on May 18, 2010 to Fitzgerald Nursuries of Kilkenny, Ireland.
Problems
No serious insect or disease problems.
Uses
Group or mass as a ground cover in part shade areas of borders or woodland gardens. Effective accent for smaller gardens. Edging plant for paths or walkways. Also appropriate for areas with moist soils such as low spots and stream/pond margins.