Everest Sedge

Oshima sedge (Carex oshimensis, Cyperaceae) is a clump-forming ornamental grass from Oshima Island, Japan, reaching about 1 foot tall and wide with a dense habit. It is valued primarily for its attractive striped or colored foliage, which provides year-round interest. Brown to copper flowering spikes appear in spring and summer. The clump increases slowly in size over years without aggressive spreading.

Oshima sedge grows in sun to part shade on rich, moist to wet soils, hardy in Zones 5a to 9b. It is deer-resistant and low-maintenance, tolerating wet soil and temporary flooding but not drought. It supports Satyr butterfly larvae and attracts songbirds and small mammals. Cultivars include 'Evergold' (RHS Award of Garden Merit winner, cream-striped), 'Everillo' (chartreuse), 'Everlime' (lime-green), and 'Carfit01.' Aphids are an occasional pest; no significant diseases are documented.