Prairie Cordgrass

Herbaceous

Prairie Cordgrass

Spartina pectinata

Also known as: Freshwater Cordgrass, Sloughgrass

Herbaceous Poaceae Erosion ControlWildlife AttractorWater RetentionBiomass
Hardiness Zone
3-9
Ideal Temp
40–95°F
Survives Down To
-40°F
Life Cycle
Perennial

Prairie cordgrass (Spartina pectinata) is a robust rhizomatous grass of North American wetlands, wet prairies, and rain-garden bottoms, forming tall clumps with narrow leaves and airy flowering panicles in summer. Culms often reach 4–7 feet (1.2–2.1 m), spreading by rhizomes into soil-stabilizing colonies where moisture is reliable. It is not the coastal saltmarsh Spartina complex—this is the inland workhorse for biofiltration, bank binding, and habitat structure in freshwater contexts. ☀️💧 Sun and Water Requirements: Full sun for strongest stems and dense stands; partial shade reduces vigor. Moist to wet soils with some organic matter mimic native sites; tolerates seasonal flooding and short dry downs once established. Avoid planting in dry xeric berms without irrigation—it will simply leave. ✂️ Propagation: Divide rhizomes in early spring before growth surges; keep divisions moist until replanted. Sow seed with consistent moisture and warmth; establishment from seed is slower than vegetative chunks. Cut back dead material in late winter to clear space for new culms. 🌾 Harvest / Best Use Timing: Cut stems for mulch or weaving crafts after seeds mature if local regulations allow—avoid removing entire stands from public land. Peak biomass tracks warm wet months. Leave standing stems over winter for cover unless fire codes or aesthetics demand otherwise.

Good Neighbors
  • Marsh Blazingstar — complementary forb color rising above shorter wet-meadow grasses
  • Swamp Milkweed — milkweed neighbor for monarch habitat in moist sun
  • Pickerelweed — emergent aquatic at the deeper water interface where cordgrass meets open water
Cautions
  • Rhizome vigor — can expand beyond tiny formal beds without edging or containers
  • Salt exposure — not a coastal saltmarsh specialist; chronic salinity selects different Spartina species
Known Threats — Organic Solutions Only
Aphids
Aphidoidea
Armyworms
Spodoptera spp.
Bamboo Mite
Schizotetranychus longus
Corn Earworm
Helicoverpa zea
Fall Armyworm
Spodoptera frugiperda
Japanese Beetles
Popillia japonica
Leaf Blight
Various Fungal Pathogens
Lubber Grasshopper
Romalea microptera
Rice Blast Fungus
Magnaporthe oryzae
Rice Water Weevil
Lissorhoptrus oryzophilus
Spider Mites
Tetranychidae
Spittlebugs
Cercopidae
Wireworm
Elateridae (larvae; e.g., Agriotes spp.)