North America Native Plant

Anderson’s Weissia Moss

Botanical name: Weissia andersoniana

USDA symbol: WEAN

Habit: nonvascular

Native status: Native to North America  

Synonyms: Weissia glauca E.B. Bartram (WEGL2)   

Anderson’s Weissia Moss: A Tiny Native Wonder for Your Rock Garden Meet Anderson’s weissia moss (Weissia andersoniana), one of nature’s most understated performers in the world of native plants. This tiny bryophyte might not win any beauty contests, but it plays a surprisingly important role in North American ecosystems and ...

Anderson’s Weissia Moss: A Tiny Native Wonder for Your Rock Garden

Meet Anderson’s weissia moss (Weissia andersoniana), one of nature’s most understated performers in the world of native plants. This tiny bryophyte might not win any beauty contests, but it plays a surprisingly important role in North American ecosystems and can add authentic character to the right garden setting.

What Exactly Is Anderson’s Weissia Moss?

Anderson’s weissia moss is a terrestrial bryophyte native to North America. Unlike the flashy flowering plants that often steal the spotlight, this humble moss belongs to an ancient group of plants that have been quietly doing their job for millions of years. You might also see it referred to by its scientific synonym, Weissia glauca, in older botanical references.

As a bryophyte, this moss is herbaceous and typically attaches itself to solid surfaces like rocks, dead wood, or other stable substrates rather than growing directly in soil. Think of it as nature’s way of adding a living carpet to otherwise bare surfaces.

Where You’ll Find This Native Moss

Anderson’s weissia moss calls western North America home, particularly thriving in the arid and semi-arid regions that stretch across much of the American West. It’s adapted to survive in challenging conditions that would leave many other plants gasping for moisture.

Is Anderson’s Weissia Moss Right for Your Garden?

Let’s be honest – this isn’t a moss you’ll typically find at your local garden center, and that’s perfectly fine! Anderson’s weissia moss is more of a happy accident than a planned garden addition. Here’s what makes it special:

  • It’s completely native to North America, supporting local ecosystems
  • Requires virtually no maintenance once established
  • Thrives in dry conditions where other ground covers struggle
  • Adds authentic character to rock gardens and xeriscaping projects
  • Helps prevent soil erosion on rocky surfaces

The Perfect Garden Settings

If you’re lucky enough to have Anderson’s weissia moss appear naturally in your landscape, consider yourself blessed with a true native gem. It’s particularly well-suited for:

  • Rock gardens with natural stone features
  • Alpine garden designs
  • Xeriscaping projects in western regions
  • Areas with exposed rocks or rocky outcroppings
  • Low-maintenance landscape designs

Growing Conditions and Care

The beauty of Anderson’s weissia moss lies in its self-sufficiency. This tough little plant prefers:

  • Well-draining, rocky substrates
  • Full sun to partial shade exposure
  • Minimal supplemental watering
  • USDA hardiness zones 4-9
  • Natural establishment rather than transplanting

Rather than trying to cultivate this moss, your best bet is to create conditions where it might naturally establish itself. Focus on providing rocky surfaces and avoiding over-watering areas where you’d like to see native mosses appear.

How to Identify Anderson’s Weissia Moss

Spotting Anderson’s weissia moss requires a keen eye, as it forms small, inconspicuous patches or appears as scattered individual plants. Look for:

  • Tiny, green to yellowish-green moss plants
  • Growth on rocks, stone walls, or wooden surfaces
  • Presence in dry, exposed locations
  • Small size compared to more common lawn mosses

The Bottom Line

Anderson’s weissia moss might not be the showstopper of your garden, but it represents something equally valuable – the quiet resilience of native plants adapted to challenging conditions. If you discover this little moss growing naturally on your property, consider it a sign that you’re providing habitat for authentic North American flora. Rather than trying to remove it, embrace its presence as part of a truly native landscape that celebrates the understated beauty of our continent’s diverse plant communities.

Anderson’s Weissia Moss

Classification

Group

Moss

Kingdom

Plantae - Plants

Subkingdom
Superdivision
Division

Bryophyta - Mosses

Subdivision

Musci

Class

Bryopsida - True mosses

Subclass

Bryidae

Order

Pottiales

Family

Pottiaceae Hampe

Genus

Weissia Hedw. - weissia moss

Species

Weissia andersoniana R.H. Zander - Anderson's weissia moss

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