The Wonderful World of Moss: Small Plants, Extraordinary Wonders

From remarkable survival abilities to miniature ecosystems, there's much more to moss than meets the eye.

I've been fascinated by moss for as long as I can remember.

Even as a child, I was drawn to the different kinds of moss growing in gardens, on old walls and between stones. I loved how different they could be. Some formed soft, rounded cushions, others spread into carpets, and some looked like miniature forests when you got close enough.

Then my terrarium hobby began, and that fascination turned into something of an obsession!

These days, I can hardly go anywhere without automatically looking for moss. I'll be walking through a garden or along a pavement and suddenly notice a species I haven't seen before. Before I know it, I'm crouching down to examine its structure, wondering what it is and whether it might grow in a terrarium.

What fascinates me most is just how different these little plants can be. Their textures, growth patterns, preferred environments and, perhaps most remarkably, their ability to survive conditions that would be disastrous for many other plants.

The more I learn about moss, the more questions I seem to have.

So I thought I'd share some of the things that make these little plants so extraordinary.

Not All Moss Is the Same

One of the first things you discover when you start paying attention to moss is the incredible variety.

From a distance, it may all look like a simple green covering, but there are more than 12,000 recognised moss species worldwide, with an astonishing range of shapes, textures and growth habits.

Some grow in dense, rounded cushions, while others spread horizontally or develop upright stems that resemble tiny trees. Their colours range from bright lime green to deep forest green, with some species displaying golden, silvery or reddish tones.

A Few Fascinating Growth Forms

Cushion mosses grow in compact, rounded clumps. Their dense structure can help retain moisture and protect the plants within the cushion.

Carpet-forming mosses spread across surfaces, creating the soft green coverings we often associate with woodland floors.

Feather mosses have delicate, branching structures that resemble miniature fern fronds.

Haircap mosses, such as species of Polytrichum, often grow upright, giving them a distinctive miniature-forest appearance.

Sphagnum mosses are particularly interesting because of their exceptional water-holding abilities and their important role in peatland ecosystems.

These descriptions refer to different groups or growth forms rather than one formal classification system. Not every moss is suitable for a terrarium, and identifying the species is often the first challenge.

That's part of the fun for me. What initially looks like an ordinary patch of green can turn out to be something completely different when examined closely.

Further reading: Australian National Botanic Gardens – What Is a Moss?

The Incredible Ability to Survive Drying Out

This is probably one of the things about moss that fascinates me most.

Have you ever noticed moss that appears completely dried out, only to become green and active again after rain?

Some mosses have a remarkable ability called desiccation tolerance, which allows them to survive losing most of their water without suffering irreversible damage.

As they dry, their metabolic activity slows dramatically. Protective mechanisms within their cells help them tolerate dehydration, and when water becomes available again, they can rehydrate and resume normal biological processes.

In some species, this recovery happens surprisingly quickly.

What makes this especially interesting is that not all mosses possess the same level of tolerance. Some species can withstand severe drying, while others depend on consistently moist environments.

This difference is important when selecting moss for terrariums. A species that survives periodic drying on an exposed wall may not appreciate permanently humid conditions inside glass.

And the reverse is equally true.

An important scientific distinction: When dried moss rehydrates and resumes activity, it isn't coming back from death. It has remained alive through dehydration, even though its biological activity was greatly reduced.

Understanding how different species respond to moisture has become one of my favourite parts of experimenting with moss.

Moss Doesn't Have True Roots

Unlike most familiar garden plants, mosses don't have true roots.

Instead, they have tiny structures called rhizoids, which primarily help anchor them to surfaces such as soil, bark and stone.

Most mosses absorb water and dissolved nutrients directly across their surfaces rather than through a conventional root system.

This helps explain why moss can establish itself in places where many other plants would struggle, provided there is sufficient moisture, light and a suitable surface.

It's also why moss responds so visibly to changes in humidity and water availability.

Some species curl their leaves inward as they dry and unfold them when rehydrated. Others change colour or texture noticeably.

Once you understand a little about how moss functions, you begin to recognise these responses rather than simply assuming that a patch has died.

Further reading: Australian National Botanic Gardens – Mosses and Their Structure

Moss Is a Miniature Habitat

Moss doesn't simply grow within an environment; it can also influence the conditions around it.

Dense moss growth helps retain moisture, protects exposed soil surfaces and provides shelter for tiny organisms.

Springtails, mites, microscopic animals, fungi and bacteria may all live among the stems and leaves, contributing to the wider ecosystem.

Moss also plays a role in nutrient cycling and soil functioning.

A fascinating study published in Nature Geoscience in 2023 examined the contribution of soil mosses to ecosystems around the world.

The researchers found that moss-covered soils were associated with greater carbon and nutrient pools, along with several other beneficial soil functions, compared with bare soils.

For plants that are so easily overlooked, their ecological contribution can be surprisingly significant.

It's also one of the reasons I enjoy combining moss with other plants and carefully selected substrate materials in terrariums. Although a terrarium cannot recreate every process found in nature, many of the same relationships between moisture, plants, microorganisms and organic matter can be observed on a smaller scale.

Explore the research: Nature Geoscience – The Global Contribution of Soil Mosses to Ecosystem Services

Sphagnum: Nature's Little Sponge

If you've ever built a terrarium, you may already be familiar with sphagnum moss.

It's one of the materials I use in many of my Living Art builds because of its remarkable water-holding properties.

Sphagnum is a genus of mosses containing specialised cells that can absorb and retain large quantities of water. Some species can hold more than 15 times their dry weight in water.

In natural peatlands, sphagnum helps maintain wet conditions and contributes to the accumulation of organic material. Over long periods, this can lead to the formation of peat, which stores significant amounts of carbon.

Living Moss Versus Dried Sphagnum

There's an important distinction between the living moss growing on the surface of a terrarium and the dried sphagnum used within its substrate layers.

Living moss grows, photosynthesises and responds to its environment.

Dried sphagnum is commonly used as a substrate component because it retains moisture and helps influence the growing conditions around plant roots.

In my terrarium builds, these materials serve different purposes.

Understanding their properties helps me choose how and where to use them rather than treating all moss as interchangeable.

Further reading: IUCN UK Peatland Programme

How Does Moss Reproduce Without Flowers?

Mosses don't produce flowers or seeds. Instead, their life cycle involves spores.

You may occasionally notice tiny stalks growing above a patch of moss, each carrying a capsule at the top.

These structures are called sporophytes, and the capsules produce spores that can disperse and, under suitable conditions, develop into new moss plants.

Mosses can also reproduce vegetatively. In some species, fragments of existing plants can establish themselves and develop into new growth.

This is particularly interesting when propagating moss for terrariums.

I've found that experimenting with different growing conditions is part of the enjoyment. Some mosses establish themselves relatively easily, while others are much more demanding.

Success depends on the species, the condition of the material and factors such as moisture, light and temperature.

Watching a small fragment gradually establish and spread is especially rewarding when you've been observing its progress over time.

Why Moss Has Become Such a Big Part of My Terrarium Hobby

When I build a terrarium, moss is rarely just a decorative finishing touch.

It helps bring the different elements of a landscape together, softening the transitions between stones, wood and plants.

Different growth forms also create different visual effects. Cushion moss can add height and structure, while spreading mosses help create continuity across the substrate.

But what interests me most is learning which species thrive under different conditions.

I've become increasingly curious about how moss responds to different surfaces, humidity levels and growing environments. Some species establish beautifully on wood, others prefer substrate or stone, and some simply don't adapt well to enclosed conditions.

Not every experiment works, and that's part of the process.

I enjoy trying to understand why something succeeded or failed rather than simply replacing it and moving on.

In many ways, working with moss has become a hobby within my terrarium hobby.

And I suspect I still have an enormous amount to learn.

Keeping Moss Happy in a Terrarium

Despite the remarkable resilience of some species, moss isn't indestructible.

Different mosses have different requirements, so there isn't one perfect set of conditions that works for every species.

Light

Many mosses suitable for tropical terrariums prefer bright, indirect light.

Direct sunlight can quickly heat a glass container and damage the plants inside, while insufficient light can also cause moss to decline.

Moisture

Moss needs moisture to remain biologically active, but not every species enjoys constantly saturated conditions.

In a balanced closed terrarium, moisture circulates through evaporation and condensation, meaning additional watering may be needed only rarely.

More open terrariums may require occasional gentle misting.

I prefer using reverse-osmosis water, particularly to avoid mineral deposits accumulating on the glass and moss.

Airflow

Some mosses thrive in consistently humid, enclosed environments, while others benefit from greater airflow.

Matching the moss to the terrarium's conditions is far more effective than trying to force every species to adapt.

Observation

This is probably the most useful advice I can give.

Rather than following a strict watering schedule, pay attention to how your moss looks and grows.

Changes in colour, texture and growth can provide clues about its condition, but they need to be interpreted carefully.

For example, yellowing or browning doesn't necessarily mean a moss needs more water. Excessive moisture, unsuitable lighting, temperature stress and natural ageing can also contribute.

Sometimes it's better to observe for a little longer before making adjustments.

Further reading: Royal Horticultural Society – Bottle Gardens and Terrariums

A Fascination That Keeps Growing

I don't think I'll ever stop being fascinated by moss.

What started as a childhood interest has become something I actively look for wherever I go. I notice differences I would never have recognised years ago, and every unfamiliar species gives me another reason to learn.

My terrarium hobby has certainly made that fascination stronger, but it's also changed how I observe the natural world.

I find myself paying closer attention to growing conditions, seasonal changes and the remarkable ways different plants respond to their environments.

And perhaps that's what I enjoy most.

Even after years of experimenting, moss still surprises me.

There's always another species to discover, another growing method to try or another question I haven't quite answered.

If this article encourages you to take a closer look at the moss growing somewhere around you, I hope you'll find it just as fascinating as I do.

Living Art, Perfectly Composed.