North America Native Plant

Lean Flatsedge

Botanical name: Cyperus setigerus

USDA symbol: CYSE3

Life cycle: perennial

Habit: grass

Native status: Native to the lower 48 states  

Synonyms: Cyperus hallii Britton (CYHA10)  âš˜  Cyperus praelongatus Steud. (CYPR12)   

Lean Flatsedge: A Humble Native Sedge for Wet Spots in Your Garden If you’ve ever wondered what to do with that perpetually soggy corner of your yard, meet lean flatsedge (Cyperus setigerus) – a modest but mighty native sedge that actually loves wet feet. While it may not win any ...

Lean Flatsedge: A Humble Native Sedge for Wet Spots in Your Garden

If you’ve ever wondered what to do with that perpetually soggy corner of your yard, meet lean flatsedge (Cyperus setigerus) – a modest but mighty native sedge that actually loves wet feet. While it may not win any beauty contests, this unassuming perennial grass-like plant has some serious practical benefits for native gardeners looking to work with nature instead of against it.

What Exactly Is Lean Flatsedge?

Lean flatsedge belongs to the sedge family (Cyperaceae), making it a grass-like plant that’s technically not a true grass at all. You might also see it listed under its former names Cyperus hallii or Cyperus praelongatus in older gardening references. As a perennial, this hardy little plant comes back year after year, slowly spreading to form colonies in suitable conditions.

Where Does Lean Flatsedge Call Home?

This sedge is a true native of the south-central United States, naturally occurring in Kansas, Missouri, New Mexico, Oklahoma, and Texas. It’s perfectly adapted to the climate challenges of this region, from scorching summers to unpredictable rainfall patterns.

Why Consider Lean Flatsedge for Your Garden?

Let’s be honest – lean flatsedge isn’t going to be the star of your flower border. But here’s why this humble plant deserves a spot in your landscape:

  • Problem solver: Thrives in those challenging wet areas where other plants struggle
  • Low maintenance: Once established, requires virtually no care
  • Erosion control: Helps stabilize soil in areas prone to washout
  • Native habitat support: Provides cover and seeds for wildlife
  • Climate adapted: Naturally suited to local weather patterns

Perfect Garden Spots for Lean Flatsedge

This adaptable sedge shines in several landscape scenarios:

  • Rain gardens: Excellent choice for managing stormwater runoff
  • Pond margins: Creates natural-looking edges around water features
  • Native plant gardens: Adds authentic local flora to your landscape
  • Naturalized areas: Perfect for low-maintenance, natural-looking spaces
  • Bioswales: Helps filter runoff in sustainable landscaping projects

Growing Conditions and Care

The beauty of lean flatsedge lies in its adaptability. This plant has a facultative wetland status, meaning it’s equally happy in wet or moderately dry conditions – though it definitely prefers the wetter end of the spectrum.

Ideal growing conditions:

  • Soil: Moist to wet soils; tolerates periodic flooding
  • Light: Full sun to partial shade
  • Hardiness: USDA zones 6-9
  • pH: Adaptable to various soil pH levels

Planting and Maintenance Tips

Growing lean flatsedge is refreshingly straightforward:

  • Planting: Spring or early fall work best for establishment
  • Spacing: Plant 12-18 inches apart for eventual coverage
  • Watering: Keep consistently moist during first growing season
  • Maintenance: Cut back to 2-3 inches in late winter before new growth
  • Spreading: Spreads naturally by underground rhizomes – control as needed

Wildlife and Ecological Benefits

While lean flatsedge may look unremarkable, it plays an important role in supporting local ecosystems. The seeds provide food for various birds, and the dense growth offers cover for small wildlife. As a wind-pollinated plant, it doesn’t attract bees and butterflies like flashy flowers do, but it contributes to the overall health of native plant communities.

Is Lean Flatsedge Right for Your Garden?

Consider lean flatsedge if you:

  • Have consistently moist or wet areas in your landscape
  • Want low-maintenance, native ground cover
  • Need erosion control for slopes or water edges
  • Are creating wildlife habitat or rain gardens
  • Appreciate the subtle beauty of native grasses and sedges

Skip this plant if you’re looking for showy flowers or need something for dry, upland areas. While it can handle some drought, lean flatsedge really shines when its roots can stay consistently moist.

Sometimes the most valuable plants in our gardens are the quiet workhorses that solve problems without making a fuss. Lean flatsedge may not be glamorous, but for native gardeners dealing with wet, challenging spots, this humble sedge just might be exactly what you’ve been looking for.

Wetland Status

The rule of seasoned gardeners and landscapers is to choose the "right plant for the right place" matching plants to their ideal growing conditions, so they'll thrive with less work and fewer inputs. But the simplicity of this catchphrase conceals how tricky plant selection is. While tags list watering requirements, there's more to the story.

Knowing a plant's wetland status can simplify the process by revealing the interaction between plants, water, and soil. Surprisingly, many popular landscape plants are wetland species! And what may be a wetland plant in one area, in another it might thrive in drier conditions. Also, it helps you make smarter gardening choices and grow healthy plants with less care and feeding, saving you time, frustration, and money while producing an attractive garden with greater ecological benefits.

Regions
Status
Moisture Conditions

Atlantic and Gulf Coastal Plain

FAC

Facultative - Plants with this status can occur in wetlands and non-wetlands

Eastern Mountains and Piedmont

FAC

Facultative - Plants with this status can occur in wetlands and non-wetlands

Great Plains

FAC

Facultative - Plants with this status can occur in wetlands and non-wetlands

Midwest

FAC

Facultative - Plants with this status can occur in wetlands and non-wetlands

Lean Flatsedge

Classification

Group

Monocot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Liliopsida - Monocotyledons

Subclass

Commelinidae

Order

Cyperales

Family

Cyperaceae Juss. - Sedge family

Genus

Cyperus L. - flatsedge

Species

Cyperus setigerus Torr. & Hook. - lean flatsedge

Plant data source: USDA, NRCS 2025. The PLANTS Database. https://plants.usda.gov,. 2/25/2025. National Plant Data Team, Greensboro, NC USA