North America Native Plant

Conostomum Moss

Botanical name: Conostomum tetragonum

USDA symbol: COTE70

Habit: nonvascular

Native status: Native to North America  

Synonyms: Conostomum boreale Sw. (COBO6)   

Conostomum Moss: A Tiny Arctic Treasure for Your Garden Have you ever wondered about those tiny green carpets that seem to appear on rocks and fallen logs? Meet conostomum moss (Conostomum tetragonum), a fascinating little bryophyte that brings a touch of the Arctic wilderness right to your backyard. While you ...

Conostomum Moss: A Tiny Arctic Treasure for Your Garden

Have you ever wondered about those tiny green carpets that seem to appear on rocks and fallen logs? Meet conostomum moss (Conostomum tetragonum), a fascinating little bryophyte that brings a touch of the Arctic wilderness right to your backyard. While you might not think of moss as a garden plant, this hardy little species has some surprising qualities that make it worth knowing about.

What Exactly Is Conostomum Moss?

Conostomum moss is a terrestrial bryophyte, which is just a fancy way of saying it’s one of those ancient, non-flowering plants that includes mosses, liverworts, and hornworts. Unlike your typical garden plants, this moss doesn’t have true roots, stems, or leaves in the traditional sense. Instead, it forms small, cushion-like patches that cling to rocks, fallen logs, and other solid surfaces rather than growing directly in soil.

You might also see this moss referred to by its scientific synonym, Conostomum boreale, in older botanical references. The name tetragonum gives away one of its most distinctive features – it refers to the four-angled shape of its spore capsules, which is pretty neat if you’re into tiny botanical details!

Where Does It Come From?

This hardy little moss is native to North America and has a special fondness for cold climates. You’ll find it naturally occurring in arctic and alpine regions, where it’s perfectly at home in the challenging conditions that would make most garden plants throw in the towel.

Is Conostomum Moss Good for Your Garden?

Here’s where things get interesting. While conostomum moss won’t attract butterflies or hummingbirds (mosses don’t produce flowers), it does offer some unique benefits for the right type of garden:

  • Creates natural-looking ground cover in rock gardens and alpine settings
  • Helps prevent soil erosion on slopes and rocky areas
  • Adds authentic texture to naturalistic landscapes
  • Requires virtually no maintenance once established
  • Provides habitat for tiny beneficial insects and microorganisms

The catch? This moss is extremely particular about its growing conditions. It thrives in cool, moist environments and prefers well-draining, rocky substrates. If you live in a warm climate or don’t have the right conditions, you’re probably better off admiring it in its natural habitat.

How to Identify Conostomum Moss

Spotting conostomum moss in the wild is like finding a tiny treasure. Look for these key features:

  • Small, dense cushions or mats, usually just a few inches across
  • Grows attached to rocks, fallen logs, or other hard surfaces
  • Four-angled spore capsules (when present) – this is the real giveaway
  • Typically found in cool, moist locations
  • Often appears in mountainous or northern regions

Creating the Right Conditions

If you’re determined to encourage conostomum moss in your landscape, you’ll need to think like an Arctic gardener. This moss thrives in USDA hardiness zones 1-6, where winters are cold and summers are cool. It needs:

  • Cool, consistently moist conditions
  • Good drainage (it hates waterlogged conditions)
  • Rocky or sandy substrate
  • Partial shade to protect from hot afternoon sun

Rather than trying to plant or propagate this moss, your best bet is to create the right conditions and see if it appears naturally. Mosses like conostomum are notoriously difficult to establish from cultivation, but they’re surprisingly good at finding suitable spots on their own.

The Bottom Line

Conostomum moss is one of those plants that’s more about appreciation than cultivation. If you’re lucky enough to have it appear in your rock garden or naturalistic landscape, consider yourself fortunate to be hosting this little piece of Arctic wilderness. While it won’t be the star of your flower beds, it adds an authentic, primordial touch that connects your garden to some of Earth’s most pristine landscapes.

Remember, the best approach with specialized mosses like conostomum is often to simply create suitable conditions and let nature do the rest. After all, these ancient plants have been thriving on their own for millions of years – they probably don’t need much help from us!

Conostomum Moss

Classification

Group

Moss

Kingdom

Plantae - Plants

Subkingdom
Superdivision
Division

Bryophyta - Mosses

Subdivision

Musci

Class

Bryopsida - True mosses

Subclass

Bryidae

Order

Bryales

Family

Bartramiaceae Schwägr.

Genus

Conostomum Sw. - conostomum moss

Species

Conostomum tetragonum (Hedw.) Lindb. - conostomum moss

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