Carex radiata

Species Native to Missouri
Common Name: eastern star sedge
Type: Rush or Sedge
Family: Cyperaceae
Native Range: Central and eastern North America
Zone: 4 to 8
Height: 2.00 to 2.50 feet
Spread: 1.50 to 2.00 feet
Bloom Time: April to May
Bloom Description: Yellowish-green
Sun: Part shade
Water: Medium to wet
Maintenance: Low
Suggested Use: Ground Cover, Naturalize, Rain Garden
Flower: Showy
Leaf: Evergreen
Other: Winter Interest
Tolerate: Wet Soil

Culture

Best grown in moist to moderately wet, organically rich loams in sun-dappled to medium shade. Tolerates close to full shade. Soils should never be allowed to dry out and need consistent supplemental watering in hot summer weather. Cut foliage close to the ground and remove as needed in late winter. Plants may be propagated by division or seed. In optimum growing conditions, plants will naturalize by self-seeding.

Noteworthy Characteristics

Carex radiata, commonly known as eastern star sedge (star-like flower clusters) or straight-styled wood sedge (tip of the female flower known as the style is straight rather than curled), is an evergreen perennial that typically produces a dense foliage clump to 8-12” tall of narrow, grass-like, medium green blades. This sedge is native to mesic to wet-mesic bottomlands and upland forests and on moist ravine slopes, sometimes in seasonally wet locations, in eastern North America from Newfoundland to Manitoba south to Missouri, Oklahoma, Arkansas, and Georgia.

Ascending to wide-spreading, triangular culms (flower stems) rise above the foliage clump in spring to 20-28” tall. Most culms are topped by an open, elongate, yellowish-green, terminal inflorescence (to 1-3” long) consisting of 3-8 flower spikelets. Each spikelet contains a star-like cluster of 3-9 perigynia (perigynum is a scale-like bract which encloses each female flower). Flowers bloom from April-May. Male flowers, if present, are borne above the female flowers on the spikes (androgynous). Female flowers are followed by tiny, ovate to obovate achenes which radiate outward from the stem in a star-like pattern. Short rhizomes are poorly-developed.

Carex radiata is very similar to and was formerly included in C. rosea.

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.

Specific epithet from Latin means radiating in reference to the developing seeds radiating outward from the stem.

Problems

No serious insect or disease problems.

Garden Uses

Group or mass as a clumping ground cover in shady areas of borders, woodland gardens or naturalized areas. Edging plant for paths or woodland areas. Also appropriate for areas with moist soils such as low spots or on the periphery of streams or ponds.