Carex macrocephala aka Large Head Sedge

Carex macrocephala, or largehead sedge, belongs to the sedge family, Cyperaceae. This perennial grows in temperate parts of the North Pacific. Its native range includes the Russian Far East and Japan. In North America, it extends from Alaska south to Oregon. It also grows along the coast of British Columbia. It is not native to Britain or Ireland.

This is a low plant, reaching about 0.7 feet (0.2 metres). Kew describes its life form as perennial or a rhizomatous geophyte. Its wild sites include coastal dunes and sandy beaches. It grows beside sounds, bays, and inlets as well. These habitats place it close to the sea. PFAF reports that the plant can withstand maritime exposure. The supplied species accounts give no detailed leaf or stem description.

PFAF gives its flowering season as April to May. Male and female flowers occur on the same plant. Wind carries pollen between the flowers. Seeds ripen from June through August, after the flowering season. The accounts do not describe the flowers' colour or shape. They also give no details about the fruit's appearance. The seeds are small, which makes food preparation awkward.

For cultivation, PFAF lists moist or wet soil as suitable. It accepts sand, loam, and clay in that account. It also accepts mildly acid, neutral, and mildly alkaline conditions. Grow it in full sun or partial shade. PFAF lists bog gardens and cultivated beds as possible settings. Its coastal habitat may also interest gardeners near the sea. British hardiness remains uncertain in the source. PFAF suggests outdoor success there but gives no confirmed rating. Its broader care notes draw partly on the genus, not this species.

PFAF lists cooked roots and seeds as edible parts. It gives the plant a low food-use rating. It reports no known hazards, but this is not a safety guarantee. No medicinal uses or other uses appear in that account. For propagation, sow seed in spring in moist soil. PFAF recommends light shade during this stage. A cold frame offers another route when seed is scarce. Seeds may sprout within two to six weeks at 15°C. Spring division provides another way to raise plants. Grow small divisions on until they have rooted well.