North America Native Plant

Slender Cottongrass

Botanical name: Eriophorum gracile var. caurianum

USDA symbol: ERGRC2

Life cycle: perennial

Habit: grass

Native status: Native to the lower 48 states  

Slender Cottongrass: A Fluffy Native Beauty for Your Water Garden If you’ve ever wondered what plant creates those delightfully fluffy, cotton-ball-like tufts swaying in wetland meadows, meet slender cottongrass (Eriophorum gracile var. caurianum). This charming native perennial brings both ecological value and whimsical beauty to gardens that can accommodate its ...

Slender Cottongrass: A Fluffy Native Beauty for Your Water Garden

If you’ve ever wondered what plant creates those delightfully fluffy, cotton-ball-like tufts swaying in wetland meadows, meet slender cottongrass (Eriophorum gracile var. caurianum). This charming native perennial brings both ecological value and whimsical beauty to gardens that can accommodate its moisture-loving nature.

What Makes Slender Cottongrass Special

Don’t let the name fool you – slender cottongrass isn’t actually a grass at all! It’s a sedge, part of the Cyperaceae family, and it’s perfectly at home in the wettest corners of your landscape. This native beauty is found naturally in California and Oregon, where it thrives in boggy meadows and marshy areas.

The real showstopper is its seed heads. After an unremarkable flowering period, this plant transforms into something magical, producing clusters of bright white, cotton-like tufts that dance in the breeze. These fluffy seed heads not only look enchanting but also help the plant disperse its seeds on the wind.

Why Grow Slender Cottongrass?

Here’s why this native sedge deserves a spot in the right garden:

  • Native plant benefits: Supporting local ecosystems while requiring less water and care once established
  • Unique aesthetic: Those cotton-ball seed heads are conversation starters that add texture and movement to water features
  • Low maintenance: Once you get the moisture levels right, this perennial pretty much takes care of itself
  • Seasonal interest: Provides structure in winter and delightful seed heads from summer through fall

Perfect Garden Settings

Slender cottongrass isn’t for every garden, but it’s perfect for these specialized spaces:

  • Bog gardens and constructed wetlands
  • Rain gardens with consistent moisture
  • Pond edges and water garden margins
  • Native plant gardens with wet areas
  • Naturalized meadow plantings in moist locations

Growing Conditions and Care

Success with slender cottongrass comes down to one key factor: moisture. This plant demands consistently wet to boggy conditions and won’t tolerate drought. Here’s what it needs to thrive:

  • Moisture: Constantly moist to wet soil – think bog conditions
  • Light: Full sun to partial shade (tolerates more shade than many wetland plants)
  • Soil: Acidic to neutral, organic-rich soils
  • Climate: Hardy in USDA zones 6-9

Planting and Care Tips

Getting started with slender cottongrass requires some planning, but the payoff is worth it:

  • Site preparation: Ensure your planting area can maintain consistent moisture year-round
  • Spacing: Allow room for gradual spreading – this sedge forms colonies over time
  • Establishment: Keep soil saturated during the first growing season
  • Maintenance: Minimal once established – just ensure consistent moisture
  • Winter care: Leave seed heads standing for winter interest and wildlife habitat

Wildlife and Ecological Benefits

While slender cottongrass is wind-pollinated and doesn’t attract many pollinators directly, it provides valuable habitat for wetland wildlife. The dense growth offers shelter for amphibians and small mammals, while the seeds may provide food for some bird species.

Is Slender Cottongrass Right for Your Garden?

This native sedge is perfect if you have a wet area that needs a beautiful, low-maintenance solution. However, it’s definitely not suitable for traditional garden beds or areas with normal soil moisture. If you’re creating a bog garden, pond edge, or working with naturally wet areas, slender cottongrass could be exactly what you need.

The key question is whether you can provide the consistently wet conditions this plant requires. If the answer is yes, you’ll be rewarded with a unique native plant that brings both ecological value and those delightfully fluffy seed heads that make every garden visitor smile.

Slender Cottongrass

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

Eriophorum L. - cottongrass

Species

Eriophorum gracile W.D.J. Koch - slender cottongrass

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