North America Native Plant

Coastal Plain Yelloweyed Grass

Botanical name: Xyris ambigua

USDA symbol: XYAM

Life cycle: perennial

Habit: forb

Native status: Native to the lower 48 states  

Coastal Plain Yelloweyed Grass: A Specialized Native Wetland Beauty If you’ve ever wondered what that delicate, grass-like plant with tiny yellow flowers is doing in wet, boggy areas across the Southeast, you’ve likely spotted coastal plain yelloweyed grass (Xyris ambigua). This charming native perennial might not be the showiest plant ...

Rare plant alert!

Region: Arkansas

Status: S2S3: Status is uncertain but is somewhere between the following rankings: Imperiled: Extremely rare due to factor(s) making it especially vulnerable to extinction. Typically 6 to 20 occurrences or few remaining individuals (1,000 to 3,000) ⚘ Vulnerable: Either very rare and local throughout its range, found only in a restricted range (even if abundant at some locations), or factors are making it vulnerable to extinction. Typically 21 to 100 occurrences or between 3,000 and 10,000 individuals ⚘

Coastal Plain Yelloweyed Grass: A Specialized Native Wetland Beauty

If you’ve ever wondered what that delicate, grass-like plant with tiny yellow flowers is doing in wet, boggy areas across the Southeast, you’ve likely spotted coastal plain yelloweyed grass (Xyris ambigua). This charming native perennial might not be the showiest plant in your garden, but it has a special role to play in wetland environments and water-wise landscaping.

What Is Coastal Plain Yelloweyed Grass?

Despite its common name, coastal plain yelloweyed grass isn’t actually a true grass at all—it’s a forb, which means it’s a non-woody perennial plant that dies back to the ground each winter and regrows from its base. This native beauty produces small, bright yellow flowers on slender stalks that rise above its grass-like foliage, creating a subtle but cheerful display from summer through fall.

Where Does It Call Home?

Coastal plain yelloweyed grass is proudly native to the southeastern United States, naturally occurring across eleven states including Alabama, Arkansas, Florida, Georgia, Louisiana, Mississippi, North Carolina, South Carolina, Tennessee, Texas, and Virginia. It thrives in the coastal plain regions where wet, acidic soils create the perfect conditions for this specialized plant.

A Word of Caution: Rarity Matters

Here’s something important to know before you start planning your wetland garden: coastal plain yelloweyed grass has a rarity status of S2S3 in Arkansas’s Coastal Plain, meaning it’s considered uncommon to rare in that region. If you’re interested in adding this native beauty to your landscape, make sure you source it responsibly from reputable native plant nurseries rather than collecting it from the wild.

Why Consider This Wetland Wonder?

You might be wondering if coastal plain yelloweyed grass deserves a spot in your garden. Here are some compelling reasons to consider it:

  • True native credentials: It’s genuinely native to the southeastern U.S., supporting local ecosystems
  • Pollinator magnet: Those small yellow flowers are perfect landing pads for native bees and other small pollinators
  • Low maintenance: Once established in the right conditions, it pretty much takes care of itself
  • Unique texture: Adds interesting vertical lines and fine texture to wetland plantings
  • Seasonal interest: Provides blooms from summer through fall when many other plants are winding down

The Perfect Garden Match

Coastal plain yelloweyed grass isn’t for every garden situation—and that’s perfectly okay! This plant is an obligate wetland species, meaning it almost always occurs in wetlands and needs consistently wet conditions to thrive. It’s ideal for:

  • Bog gardens and constructed wetlands
  • Rain gardens with poor drainage
  • Pond edges and water feature margins
  • Wetland restoration projects
  • Naturalized areas with wet soils

Growing Conditions: Wet, Wet, Wet!

If you’re thinking about growing coastal plain yelloweyed grass, here’s what you need to know about keeping it happy:

  • Sunlight: Prefers full sun for best flowering
  • Soil: Needs consistently moist to wet, acidic soils (pH 4.5-6.0)
  • Water: This is non-negotiable—it must have consistent moisture or standing water
  • Hardiness: Suitable for USDA zones 7-10
  • Drainage: Paradoxically, it needs poor drainage or areas that stay wet

Planting and Care Tips

Successfully growing coastal plain yelloweyed grass is all about understanding its wetland nature:

  • Choose the right spot: Look for the wettest, soggiest area of your property
  • Soil prep: If your soil isn’t naturally acidic, you may need to amend it
  • Planting time: Spring is ideal for getting new plants established
  • Watering: Keep soil constantly moist—this plant should never dry out
  • Fertilizing: Generally unnecessary; these plants are adapted to nutrient-poor wetland soils
  • Maintenance: Very low—just cut back dead foliage in late winter

Is This Plant Right for You?

Coastal plain yelloweyed grass is definitely a specialized plant for specific situations. Consider it if you have consistently wet areas where other plants struggle, you’re creating a rain garden or bog garden, or you’re working on wetland restoration. However, skip it if you have typical garden soil that drains well or if you’re looking for a low-water plant—this beauty needs the opposite!

Remember, if you decide to grow coastal plain yelloweyed grass, source it responsibly from native plant nurseries to help protect wild populations. Your wet, boggy corner of the garden might just become a haven for native pollinators and a testament to the beauty of working with nature’s preferences rather than against them.

Coastal Plain Yelloweyed Grass

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

Commelinales

Family

Xyridaceae C. Agardh - Yellow-eyed Grass family

Genus

Xyris L. - yelloweyed grass

Species

Xyris ambigua Bey. ex Kunth - coastal plain yelloweyed grass

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