North America Native Plant

Andrews’ Rhizomnium Moss

Botanical name: Rhizomnium andrewsianum

USDA symbol: RHAN70

Habit: nonvascular

Native status: Native to North America  

Synonyms: Mnium andrewsianum Steere (MNAN)   

Andrews’ Rhizomnium Moss: A Tiny Native Treasure for Shady Spaces Meet Andrews’ rhizomnium moss (Rhizomnium andrewsianum), a delightful little native that’s probably already living in your neighborhood—you just might not have noticed it yet! This petite moss is one of those garden gems that works quietly behind the scenes, adding ...

Andrews’ Rhizomnium Moss: A Tiny Native Treasure for Shady Spaces

Meet Andrews’ rhizomnium moss (Rhizomnium andrewsianum), a delightful little native that’s probably already living in your neighborhood—you just might not have noticed it yet! This petite moss is one of those garden gems that works quietly behind the scenes, adding subtle beauty and ecological value to shaded corners of your landscape.

What Exactly Is Andrews’ Rhizomnium Moss?

Andrews’ rhizomnium moss is a terrestrial moss native to North America, which means it’s perfectly at home growing on soil, rocks, or even fallen logs in your garden. Unlike the flowering plants we’re used to thinking about, this little guy reproduces through spores rather than seeds, and it doesn’t need fancy pollination strategies to get the job done.

You might also see this moss referenced by its scientific synonym, Mnium andrewsianum Steere, in older botanical references. But don’t let the fancy names intimidate you—this is simply a charming, low-maintenance addition to any shade garden.

Where Does It Call Home?

This moss is a true North American native, with its primary range in the Pacific Northwest region. You’ll find it naturally occurring in British Columbia and the northwestern United States, where it thrives in the region’s famously moist, temperate conditions.

Spotting Andrews’ Rhizomnium Moss in Your Garden

Here’s what to look for when trying to identify this moss:

  • Small, delicate plants that form low, carpet-like patches
  • Distinctive leaf arrangement in rosette patterns
  • Bright green color when moist, may appear duller when dry
  • Typically found growing on soil, rocks, or decaying wood
  • Prefers shaded, consistently moist locations

Why Your Garden Will Love This Little Moss

While Andrews’ rhizomnium moss might not provide nectar for butterflies or dramatic seasonal color changes, it offers some wonderful benefits that make it worth celebrating:

  • Natural ground cover: Creates a living carpet in areas where traditional plants struggle
  • Erosion control: Helps stabilize soil on slopes and around water features
  • Moisture regulation: Acts like a natural sponge, helping to maintain consistent soil moisture
  • Habitat creation: Provides microhabitat for tiny beneficial insects and other small creatures
  • Year-round interest: Stays green and attractive throughout most of the year

Perfect Spots for This Native Moss

Andrews’ rhizomnium moss thrives in USDA hardiness zones 5-9, making it suitable for a wide range of North American gardens. It’s particularly happy in:

  • Woodland gardens with dappled shade
  • Rock gardens with consistent moisture
  • Shaded areas around water features
  • North-facing slopes that stay cool and moist
  • Areas under large trees where other plants struggle

Encouraging This Moss in Your Landscape

The beautiful thing about native mosses like Andrews’ rhizomnium is that they often show up on their own when conditions are right. Rather than planting this moss in the traditional sense, you can encourage its natural establishment by:

  • Creating the right conditions: Maintain consistent moisture in shaded areas
  • Avoiding disturbance: Minimize foot traffic and soil disruption in potential moss habitat
  • Reducing competition: Remove aggressive weeds that might overwhelm delicate moss colonies
  • Being patient: Moss establishment takes time—sometimes several seasons

The Bottom Line

Andrews’ rhizomnium moss might be small, but it’s a perfect example of how native plants—even the tiniest ones—can contribute to a healthy, beautiful garden ecosystem. If you’re lucky enough to discover this little moss establishing itself in your shaded garden areas, consider yourself blessed with a low-maintenance native that’s doing important ecological work while adding subtle natural beauty to your landscape.

Remember, the best gardens often include a mix of plants at every scale, from towering trees down to humble mosses. Andrews’ rhizomnium moss proves that sometimes the smallest players make the biggest difference in creating a truly sustainable, native landscape.

Andrews’ Rhizomnium Moss

Classification

Group

Moss

Kingdom

Plantae - Plants

Subkingdom
Superdivision
Division

Bryophyta - Mosses

Subdivision

Musci

Class

Bryopsida - True mosses

Subclass

Bryidae

Order

Bryales

Family

Mniaceae Schwägr.

Genus

Rhizomnium (Broth.) T. Kop. - rhizomnium moss

Species

Rhizomnium andrewsianum (Steere) T. Kop. - Andrews' rhizomnium moss

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