Cave Plants To Identify When You Go Spelunking

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Beware: You should never explore wild caves alone or without proper gear. Consider getting in touch with a Grotto of the National Speleological Society at or a qualified cave club. These groups are skilled and will train you. Without sufficient knowledge, preparation, and equipment, cave exploring can lead to serious injury or death.

Caves are fascinating places. The air is cool and damp, and it’s quiet. Cave plants have adaptations that allow them to grow in nutrient-poor soil and low light levels.

These adaptations include roots that absorb nutrients from rock fissures, stems that become woody when exposed to the sun, or leaves that turn black when they die. Some cave plants include mosses, ferns, algae, and lichens which grow on rocks too dry for most other plants to survive in.

Cave Plants and Sunlight Gradation

Cave plants are a special breed adapted to grow in the low light of caves and aren’t well-adapted to the sun’s light.

In fact, there is a gradual transition from sunlight to darkness in caves, and this gradient can vary depending on how deep you go into a cave system.

Some plants can survive in either environment. Explorers find them floating on pools of water in chambers with high humidity and little light.

On the other hand, some plants grow in the dark and require no light at all. Some call them “cave-adapted”. These unique plants have adapted to live in total darkness and may be found growing on walls, ceilings, stalagmites, and other surfaces.

If you love them enough to want them in your backyard, some of these plants are available both as full plants or seeds for you to plant.

Let’s take a look now, at what you might find at the next cave you visit.


A close up of Saxifrage, perennial plant that can be found growing outside a cave.
These flowers can be found growing outside cave entrances.

Saxifrage is a perennial plant that grows in the wild in North America, Europe, Asia, and Africa. It is a member of the saxifragaceae family, and its flowers are white or pink. The leaves are small, round, and smooth.

The flowers are tubular, with five petals and a star-shaped center. The plant grows to about 40 inches tall.

The image to the right shows the bright pink color of the Saxifraga Rose Robe plant. Depending on where you go, you may find this variation instead.

A picture shows a bundle of growing Saxifrage Rose Robe plants.

You can order Burnet Saxifrage seeds from Amazon, as well as Saxifraga Rose Robe if you prefer the pink.

Wood Sorrel

An image of the plant called wood sorrel,

Wood Sorrel is a perennial plant that grows in the wild, but can be found by cave entrances. Other names for this plant include Oxalis Acetosella, sourgrass, and wood sour. Wood Sorrel is a member of the Oxalidaceae family and has small, yellow flowers.

It is native to Europe and North America and grows in woodlands, meadows, and gardens. Due to the acidic nature of the soil by cave entrances, most plants cannot thrive here. Wood sorrel is one of a few exceptions.

Etsy offers beautiful wood sorrel bareroot seedlings here.

Herb Robert

Herb Robert is a perennial plant that grows in shady areas in the wild, and it has a yellow flower with five petals. It is also known as Herb-Robert and Spring Rocket, but it is not related to the plant Rocket Salad.

Herb Robert’s scientific name is Geranium robertianum, which means “Robert’s Daisy” or “Robert’s Geranium.” It is part of the Mustard family, along with chives, garlic mustard, and radishes.

It can reach heights of up to 30 cm (12 inches).

You can purchase Herb Robert seeds on Etsy here.


Moss is one of the most common types of cave plants. It is a primitive plant that reproduces by spores, and its leaves are usually thin and hair-like.

Mosses can live in damp places like caves because they have no true roots or stems necessary for photosynthesis. They absorb moisture through their leaves or directly from the air.

Mosses are bryophytes (from the Greek word meaning “mossy”), which means they are non-vascular plants with green stems and leaves that look like scales rather than blades like typical angiosperms (flowering plants).

Bryophytes do not produce flowers or fruits but reproduce via spores; this makes them unique among vascular plants because all other seed-bearing plants rely on sexual reproduction involving pollen grains fertilizing eggs inside a flower before producing seeds.


Lichens are not plants, but they are an example of a composite organism. They’re actually a symbiotic relationship between a fungus and an alga.

Lichens are found in various environments, including cold mountain slopes and caves. This is because they easily survive extreme conditions, including shallow temperatures, high winds, and drought.

What you may not know is that lichens have been around for millions of years. Over 15,000 species of lichen exist. Some lichens can be used to clean up pollution in the environment, and play roles in our food, medicine and the dyeing of cloth.


Liverworts are non-vascular plants, and they are tiny, so they can live in small places. An ancient plant, they have been around for eons. Therefore, they are well adapted to living in dark areas and many climates.

Unrelated to mosses or ferns, liverworts are very small and don’t have any leaves or stems. They have a flat appearance because they grow in two dimensions, not three like most plants.

Liverworts also lack roots and vascular tissue, so they can’t move around like plants with those features can. Instead, liverworts rely on water currents to bring nutrients from their environment.


Maidenhair Spleenwort

Maidenhair Spleenwort is a delicate, light-green herbaceous fern that grows in caves’ moist, dark environments. Scientists call it an Herbaceous perennial plant. This is the common name for plants that die back each winter and regrow from their roots in the following spring.

Maindehair spleenwort grows as tall as three feet and have left approximately 0.5 inches long. It may also have small white flowers at the end of its stems during springtime.

Brittle Bladder-Ferns

Brittle Bladder-Ferns are a type of fern that propagate by spores and grow in cold and damp conditions.

They belong to the genus Cystopteris, which contains about 50 species in North America. The most common Brittle Bladder-Fern species, C. fragilis, often grows in caves across the eastern United States.

Brittle bladder ferns have small round leaves that resemble tiny grass blades. However, they differ from other types of vegetation. Their leaves appear in bundles at the end of each stem, instead of scattered throughout.

Their stems also appear brittle and easily breakable when handled because they lack chlorophyll for photosynthesis (which means they need nutrients from outside sources).

Hart’s Tongue Ferns

Hart’s Tongue Ferns (Phyllitis scolopendrium) are native to the UK, Ireland, and Europe. Cavers can identify them by their preference for growing in damp moss-covered rocks and soil, especially in shaded areas.

Hart’s Tongue Ferns have a dark green stipe (leaf stalk) with an orange-red underside. As shown in the image below, this gives it its namesake appearance.

A hardy plant that doesn’t need much light to grow, Hart’s Tongue Fern is ideal for gardens. Plant it in the shade or even on the walls. They can also thrive indoors, provided adequate humidity and moisture levels.

Dog Violet

Dog Violet (Viola canina) is a perennial native to the UK, Europe, and North America. It produces purple flowers with yellow centers in spring and summer, growing up to 20 cm tall.

The leaves are hairy and heart-shaped with a serrated edge. This plant can grow in full sun or shade, though it prefers part shade under trees or tall shrubs or in dimmer environments like caves.

A close up of the plant Dog Violet, which can be found growing by cave entrances.


It’s a common misconception about plants, that they only grow in the sun. People who have not visited caves often assume that they are dark and void of most life.

But while the plants that grow in caves are often different, they can still be quite beautiful. They are also helpful for humans because they can be used as medicines or food sources. Knowing how to recognize some of these provides cavers with another way to learn about the environment on a caving trip.

While identifying these plants, you may also encounter some interesting cave animals, which you can read about here.

Let us know what you find, next time you enter the caves.

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