Selaginella kraussiana is a diminutive, creeping plant that brings a lush, prehistoric texture to shaded spaces. Often called spreading clubmoss or Krauss’s spikemoss, this plant is a favorite for terrariums, fairy gardens, and shady ground cover.
It’s not a true moss but a primitive vascular plant related to ferns. Its delicate, trailing stems and tiny, scale-like leaves create a beautiful carpet of green.
This guide will show you everything you need to know to successfully grow and care for this unique plant. We’ll cover its ideal conditions, propagation methods, and solutions to common problems.
Selaginella Kraussiana
Selaginella kraussiana belongs to the ancient group of plants known as lycophytes. These plants have been around for hundreds of millions of years, predating even the dinosaurs.
Its common name, clubmoss, is a bit misleading, as it is not closely related to true mosses. It’s a more complex plant with a simple internal vascular system for moving water.
There are several popular cultivars you might encounter. The most common is the vibrant green species. ‘Aurea’ or ‘Gold Tips’ has beautiful golden-yellow new growth. ‘Brownii’ is a more compact, cushion-forming variety.
Botanical Profile And Origins
This plant is native to moist, shaded areas in parts of Africa and the Azores. In the wild, it forms extensive mats on forest floors, on rocks, and along stream banks.
It thrives in high humidity and consistent moisture. Understanding its natural habitat is the key to replicating those conditions in your home or garden.
The stems root freely as they creep along the soil surface. This growth habit makes it an excellent choice for covering soil in potted plants or creating a living carpet.
Key Identifying Features
- Growth Habit: Low-growing, mat-forming, with creeping or trailing stems.
- Foliage: Tiny, bright green, scale-like leaves arranged in four rows along the stem.
- Texture: The foliage is soft and fern-like, creating a dense, mossy appearance.
- Roots: Produces tiny adventitious roots (rhizophores) along the stems that anchor into soil.
- Spores: Reproduces via spores contained in small cones (strobili) at stem tips, unlike seeds.
Ideal Growing Conditions
To keep your Selaginella kraussiana healthy, you need to mimic its preferred environment. The main pillars are consistent moisture, high humidity, and protection from strong light.
Getting these elements right will prevent most issues. This plant can be somewhat finicky if its basic needs are not met, especially regarding air moisture.
Light Requirements
This plant is a shade-lover. It prefers indirect, filtered light or deep shade. Direct sunlight, especially the hot afternoon sun, will quickly scorch its delicate leaves, causing them to turn brown and crispy.
Ideal locations include north-facing windows, areas under larger plants, or spots several feet back from an east or west window. In a terrarium, use low to medium-intensity artificial plant lights.
Soil and Potting Mix
The right soil is crucial for moisture management. Selaginella kraussiana needs a mix that retains water but also drains well to prevent soggy roots.
A standard potting mix is too heavy on its own. You should amend it to increase aeration and moisture retention. Here is a simple recipe you can use:
- Start with two parts high-quality peat moss or coco coir.
- Add one part perlite or coarse horticultural sand for drainage.
- Mix in one part fine orchid bark or vermiculite for structure and extra moisture holding.
- A handful of horticultural charcoal can help keep the mix fresh in closed environments like terrariums.
Watering and Humidity
This is the most critical aspect of care. Selaginella kraussiana must never dry out completely. The soil should feel consistently damp to the touch, like a well-wrung sponge.
However, it should not sit in waterlogged soil, as this can lead to root rot. Water thoroughly when the top surface of the soil just begins to feel slightly less moist.
Humidity is equally important. It thrives in 70% humidity or higher. Average home humidity is often too low, leading to brown, crispy leaf tips. Here are ways to increase humidity:
- Place the pot on a pebble tray filled with water.
- Group it together with other humidity-loving plants.
- Use a room humidifier nearby.
- Grow it in a sealed or partially open terrarium or cloche, which is often the best solution.
Temperature Range
This plant enjoys moderate, stable temperatures similar to a comfortable home environment. Aim to keep it between 60°F and 75°F (15°C – 24°C).
It is not cold-hardy and will suffer damage if exposed to temperatures below 50°F (10°C). Avoid placing it near cold drafts, air conditioning vents, or hot radiators, which can create dry, stressful conditions.
Planting and Propagation
Starting new plants from an existing Selaginella kraussiana is straightforward. The plant’s natural creeping habit makes it easy to propagate.
You can create new plants for other areas of your home or share them with friends. The best time to propagate is during the active growing season in spring or early summer.
How To Propagate By Stem Cuttings
This is the simplest and most reliable method. You are essentially taking a piece of the runner and encouraging it to root.
- Select a healthy, trailing stem that is several inches long.
- Using clean, sharp scissors, cut a section that is 3 to 4 inches long.
- You can remove the lower leaves from the bottom inch of the cutting if you wish, but it’s not strictly necessary.
- Prepare a small pot with the moist potting mix described earlier.
- Lay the cutting horizontally on the soil surface, or insert the cut end slightly into the mix. The stems will root from the nodes (the points where leaves emerge).
- Gently press the cutting so it has good contact with the soil.
- Cover the pot with a clear plastic bag or place it inside a propagation box to maintain very high humidity.
- Place it in a warm spot with bright, indirect light.
- Keep the soil consistently moist. Roots should begin to form within a few weeks, and new growth will appear shortly after.
Propagation By Division
If your plant has grown into a dense mat, you can divide it. This is a quick way to get a larger new plant immediately.
Gently remove the entire plant from its pot. Carefully tease apart sections of the mat, ensuring each division has plenty of stems and some roots attached. Pot each division into its own container with fresh soil, water well, and keep humid while they re-establish.
Planting As Ground Cover
In warm, humid climates (USDA zones 9-11), Selaginella kraussiana can be grown outdoors as a perennial ground cover in full shade. Prepare the soil by enriching it with organic matter like compost to improve moisture retention.
Space small plant divisions about 6 to 8 inches apart. They will quickly spread and fill in the area. Water regularly to establish and during dry periods, as it is not drought-tolerant.
Ongoing Care and Maintenance
With the right location, caring for Selaginella kraussiana is mostly about monitoring moisture and humidity. It is a relatively low-maintenance plant once its environment is stabilized.
Fertilizing Guidelines
This plant is not a heavy feeder. In fact, too much fertilizer can burn the delicate roots and stems. Use a balanced, water-soluble fertilizer (like a 10-10-10 formula) diluted to half or even quarter strength.
Apply this weak solution once a month during the spring and summer growing season. Do not fertilize at all during the fall and winter when growth naturally slows. In the nutrient-limited environment of a terrarium, fertilizing is rarely needed.
Pruning And Shaping
Pruning is simple and helps maintain a dense, tidy appearance. You can trim back any overly long or straggly stems using clean scissors.
This trimming encourages the plant to branch out and become bushier. The cuttings you remove can be used for propagation, so nothing goes to waste. Regularly remove any yellow or brown stems to keep the plant looking its best.
Repotting Schedule
Repot your Selaginella kraussiana when it becomes root-bound or when the mat of growth has completely covered the pot’s surface and is spilling over. This is typically needed every 2 to 3 years.
Choose a new pot that is only slightly larger, as too much extra soil can stay wet and cause problems. Gently loosen the root mass and place it in the new pot with fresh potting mix. Water thoroughly after repotting and provide high humidity to reduce transplant shock.
Troubleshooting Common Problems
Even with good care, you might encounter some issues. Most problems are related to water, light, or humidity.
Leaves Turning Brown Or Crispy
This is the most common complaint. It is almost always caused by low humidity or the soil drying out. The air in our homes is often too dry for this moisture-loving plant.
Increase humidity using the methods listed earlier. Check the soil moisture more frequently; it should never feel dry. Browning can also be caused by too much direct sunlight, so reassess its light exposure.
Yellowing Leaves Or Stems
General yellowing can be a sign of overwatering and potential root rot. If the soil feels constantly soggy, you may be watering too often or the potting mix may not be draining well.
Allow the soil to dry out just a tiny bit more between waterings. Ensure the pot has drainage holes. In severe cases, you may need to repot the plant into fresh, well-draining soil after trimming away any black, mushy roots.
Leggy Or Sparse Growth
If the stems are growing long with large gaps between leaves, the plant is not getting enough light. While it loves shade, it still needs bright indirect light to grow compactly.
Move it to a brighter location, but avoid direct sun. Pruning back leggy stems will also encourage fuller growth from the base.
Pests And Diseases
Thankfully, this plant is not highly susceptible to pests, especially when grown indoors. However, in dry conditions, it can occasionally attract spider mites.
Look for fine webbing and stippled, pale leaves. Increase humidity and rinse the plant gently with water or treat with insecticidal soap. Fungal gnats can be a nuisance if the soil is kept too wet. Let the soil surface dry slightly between waterings and use sticky traps.
Root rot is the main disease threat, caused by overwatering. Prevention through proper watering and a well-draining mix is the best cure.
Design Ideas and Uses
Selaginella kraussiana’s unique texture and trailing habit make it incredibly versatile in plant design. It’s a staple for creating miniature landscapes.
Terrariums And Fairy Gardens
It is arguably the perfect terrarium plant. Its small scale, love for humidity, and slow growth make it ideal for sealed or open glass containers. Use it as a lush base layer or “lawn” in your miniature scene. It pairs beautifully with other small plants like fittonia, miniature ferns, and peperomia.
Living Mulch And Pot Topper
In a large houseplant pot, you can plant Selaginella kraussiana around the base of a taller plant, like a fiddle leaf fig or a dracaena. This creates a beautiful, living mulch that helps retain soil moisture and adds visual interest at the pot’s base. Just ensure both plants have similar water and light needs.
Hanging Baskets And Shelves
In a sufficiently humid room, like a bathroom with a window, you can grow it in a shallow hanging basket. Its stems will gracefully cascade over the edges, creating a waterfall of green. It also looks lovely on a shelf where its trailing stems can creep down.
Outdoor Shade Gardens
In suitable climates, use it to fill in shady, moist spots where grass struggles. It works well between stepping stones, along shaded pathways, or under trees. Be aware that it can spread vigorously in ideal outdoor conditions, so plant it where you don’t mind it filling in.
Frequently Asked Questions
Is Selaginella Kraussiana Safe For Pets?
Yes, Selaginella kraussiana is generally considered non-toxic to cats and dogs according to the ASPCA. It is not known to contain harmful compounds that pose a risk to pets if ingested. However, it’s always best to discourage pets from chewing on any houseplants.
How Fast Does Spreading Clubmoss Grow?
Under ideal conditions of warm temperatures, high humidity, and consistent moisture, Selaginella kraussiana can grow at a moderate pace. It will steadily spread to fill a container or garden area within a single growing season. Growth slows significantly in lower light or during the cooler winter months.
Can I Grow Krauss’s Spikemoss In Water?
While some people have success rooting stem cuttings in water, it is not ideal for long-term growth. The plant prefers a moist, airy substrate. Prolonged growth in water alone can lead to weak, nutrient-deficient plants and eventual rot. It is better grown in a suitable soil mix.
Why Is My Selaginella Turning White Or Pale?
A pale or whitish appearance is usually a sign of too much light. The leaves are getting bleached. Move the plant to a shadier location immediately. In rare cases, extreme nutrient deficiency could cause paleness, but light is the most likely culprit for this specific symptom.
What Is The Difference Between Selaginella And True Moss?
This is a common point of confusion. True mosses (Bryophytes) are non-vascular plants; they absorb water directly through their leaves and have very simple structures. Selaginella (a Lycophyte) has a primitive vascular system of xylem and phloem to transport water and nutrients, similar to ferns and higher plants. This makes Selaginella more complex and generally larger than true mosses.