Lichen, the Quiet Alchemists of Stone and Air

Lichen is the hush between tree and rock. It stains bark like spilled tea, dusts granite with pale greens, and turns clean air into color. Not a plant, not a single organism, but a partnership of fungi with algae or cyanobacteria, lichen is cooperation made visible.

Delicate lichen adorns a branch, capturing the soft glow of sunlight and transforming clean air into vibrant hues of green.

What lichen is, in plain terms

Lichen is a remarkable and intricate organism that represents a symbiotic relationship primarily between fungi and photosynthetic partners, which can be either algae or cyanobacteria. In this unique partnership, the fungus plays a crucial role by constructing a protective structure, often referred to as the "house," which not only provides shelter but also helps retain moisture in the often harsh environments where lichens are found. This damp environment is essential for the survival of the entire organism, as it allows the photosynthetic partner to thrive.

The algae or cyanobacteria, on the other hand, are the primary producers in this relationship. Through the process of photosynthesis, they convert sunlight into energy, producing organic compounds that serve as food for both themselves and the fungal partner. This collaboration is a perfect example of nature's ability to adapt and thrive in ecosystems where few other organisms can survive, such as on bare rock surfaces, tree bark, or even in arctic tundras.

In the wild, lichens exhibit a fascinating variety of forms, and you will commonly encounter three broad shapes that characterize their appearance:

• Crustose: These lichens present as painted-on crusts that tightly hug surfaces such as rock or bark. They often appear as a thin, colorful layer that can be difficult to distinguish from the substrate to which they adhere. Crustose lichens are incredibly resilient, often withstanding extreme weather conditions, and they play a vital role in the weathering of rocks, contributing to soil formation over time.

• Foliose: Foliose lichens have a leaf-like structure, characterized by lobes that lift at the edges, giving them a more three-dimensional appearance. These lichens can often be peeled away from their substrate, much like leaves from a tree. Their structure allows for increased surface area, facilitating greater absorption of moisture and nutrients from the air, which is essential for their survival in various environments.

• Fruticose: These lichens resemble tiny shrubs or threads that branch out into the air, creating a more complex and three-dimensional form. Fruticose lichens often have a more delicate structure and can be found hanging from trees or growing upright from the ground. Their bushy appearance not only makes them visually striking but also enhances their ability to capture moisture and nutrients from the atmosphere.

Why lichen matters

• Natural air clues. Many lichens are sensitive to pollution. Rich lichen growth often hints at cleaner air.

• Soil starters. Lichens slowly weather rock into the first grains of soil, a patient craft measured in decades.

• Microhabitats. Insects shelter in them. Birds weave them into nests. They are texture, shelter, and snack, all in one quiet weave.

Lichen and moss, friendly neighbors

You will often find lichen and moss sharing bark and stone. They like many of the same conditions, cool and humid with dappled light. They are not partners the way lichen’s fungus and algae are. Think neighbors, not roommates.

In a delicate balance of moisture and light, lichen and moss thrive together, creating a lush green tapestry.

You will often find lichen and moss sharing bark and stone in a fascinating display of nature's resilience and adaptability. These organisms thrive in environments that provide the right conditions for their growth, which typically include cool and humid climates, along with dappled light filtering through the canopy of trees or other overhead structures. The interplay of moisture and light creates an ideal habitat for both lichen and moss, allowing them to flourish side by side. However, it is essential to understand that while they may occupy the same space, lichen and moss do not engage in a symbiotic relationship like the one seen between lichen’s fungal and algal components. Instead, they coexist as neighbors, each contributing to the ecosystem in their own unique ways without relying on one another for survival.

A close-up view of a lichen-covered branch, showcasing the intricate symbiotic relationship between fungus and photosynthetic algae or cyanobacteria in a natural woodland setting.

Moss, a non-vascular plant, absorbs water and nutrients directly from the air and the surfaces it grows on, whereas lichen is a composite organism formed from a symbiotic relationship between a fungus and photosynthetic algae or cyanobacteria. This distinction highlights the different biological processes and adaptations that allow both lichen and moss to thrive in similar environments.

Mosses often form lush, green carpets on the ground or on the surfaces of trees, while lichens can appear in a variety of colors and textures, often growing as crusty patches or leafy structures on rocks and bark. In this way, they both contribute to the biodiversity and aesthetic appeal of their habitats, creating a rich tapestry of life that can be observed in forests, on rocks, and along the edges of streams. Furthermore, the presence of lichen and moss can indicate important environmental conditions.

For instance, the health of these organisms can serve as bioindicators, signaling the quality of the air and moisture levels in their surroundings. Their ability to absorb pollutants makes them valuable in ecological monitoring, as changes in their populations can reflect shifts in environmental health. Thus, while they may not be partners in the traditional sense, lichen and moss play crucial roles in their ecosystems and demonstrate the beauty of coexistence in nature.

Can lichen live in terrariums

Sometimes. Lichen is slow-growing and particular. It prefers steady airflow and gentle humidity rather than constant wetness. Closed, steamy terrariums are better for moss. If you include lichen, use an open vessel or a bowl garden with good air movement and bright, indirect light. Mist lightly and infrequently. Allow surfaces to dry between mists.

A note on ethics. Lichens grow slowly and many sites are protected. Do not harvest from parks or public land. If a piece is already on fallen bark from private land with permission, you can place that bark in your display. Otherwise, admire lichen where it lives and let time keep its work.

Cultivating a lively terrarium: Guaranteeing that lichen flourishes in an open container with excellent air circulation and indirect lighting.

Simple care tips

• Light, bright but not harsh sun. Aim for bright, indirect light. In Australia, a south or east window is usually gentle. North can be too strong, so pull back a metre or use a sheer curtain. If using a grow light, keep it higher than moss prefers and run it fewer hours. You want clarity, not scorch.

• Air, more breeze than a closed terrarium provides. Lichen likes calm, steady airflow. Use open bowls, trays, or jars without lids. If glass is non-negotiable, leave the lid off most of the time or prop it slightly to vent. A tiny desk fan on low, pointed past the display, helps keep surfaces dry between light mists.

• Water, a fine mist when surfaces look dry. No soaking. Mist lightly, then let everything dry. Think dew, not rain. In summer heat, that might be a quick mist every few days. In cooler months, once a week or less. Use rainwater or dechlorinated tap water to avoid residue. Signs you are overdoing it, algal film, sour smell, or lichen going translucent and mushy.

• Surfaces, rough bark or stone, not potting mix. Lichen wants texture to grip. Try untreated hardwood bark, cork, or dense rock like granite or basalt. Avoid soil and constantly damp substrates. If you bring in bark, give it a dry brush, then a day of air to evict hitchhikers. Place lichen high on the hardscape where it stays drier and gets light.

  
  

Quick troubleshoot

• Edges crisping, too much sun or too little humidity. Pull back from the window and mist lightly.

• Surface slime or fuzzy mold, airflow is low or watering is heavy. Increase ventilation and skip misting until dry.

• Color fading, light is too low. Move closer to bright light without direct midday sun.

• If growth slows or turns brown, the primary suspect is often light. Insufficient light causes moss to become dull and lose its vibrancy. The ideal condition is indirect, filtered light. Consider south or east-facing windows with sheer curtains or use low-wattage grow lights on a timer.

Excessive light makes moss dry out, retracting like a snail in the sun.

Where this meets Of Forest & Fog

Our Live Wildcrafted Moss Bundles focus on healthy, humidity-loving mosses. They sometimes arrive with incidental lichen on bark or twigs. Treat that lichen as a decorative accent in open arrangements, not as a centerpiece in sealed glass. For closed builds, choose moss-rich layouts and keep lichen on display trays or open jars nearby.

Live Wildcrafted Moss Bundle (Small or Large)

FromA$21.00

BUY NOW

Explore:

• Tiny Forest Terrarium Kits for moss-first builds. (Coming Soon)

• Forest Care Guide Flipbook for set-up, watering, and troubleshooting.

• Live Wildcrafted Moss Bundles for sustainable, hand-curated textures.

Click Here To Check Out Our Care Guide