How to Grow and Care for Rainbow Moss

Rainbow Moss, known scientifically as Selaginella uncinata, is also called Peacock Moss due to the iridescent, blue-green shimmer of its foliage. This striking coloration makes it a popular choice for terrariums and shaded garden areas. Native to southern China, this plant is not a true moss but a type of lycophyte, an ancient group of vascular plants. Its low-growing, spreading habit creates a dense mat of delicate, fern-like leaves.

Ideal Growing Conditions for Rainbow Moss

The plant’s signature iridescence is most pronounced in low, indirect light. Direct sunlight should be avoided as it can scorch the delicate foliage, causing it to lose its vibrant color and potentially causing permanent damage. An ideal location receives gentle, filtered light, such as that found on a forest floor or in a shaded nook of a garden.

Consistent moisture is another requirement for this plant. The soil should be kept evenly moist but not waterlogged. Testing the soil every couple of days with a finger is a good way to gauge its moisture level. When grown indoors as a houseplant, a thorough soaking during watering sessions is beneficial.

High humidity is greatly appreciated by Rainbow Moss, which thrives in environments with 50-90% humidity. In a home setting, this can be achieved by placing the plant in a terrarium, which naturally traps moisture. Alternatively, regular misting or placing the pot on a pebble tray filled with water can help increase the ambient humidity around the plant.

The choice of substrate is also important for moisture retention and aeration. A peat-free, loam-based compost with added leaf mould is a suitable medium. A mix designed for ferns, which is both moisture-retentive and well-aerated, also works well. Some growers have success using sphagnum moss as a growing medium, as it helps maintain the consistent moisture the plant needs.

Rainbow Moss is adaptable to a range of temperatures, although it prefers warmer conditions. It is comfortable in a temperature range of 55-80°F (12-26°C). While it can tolerate cooler temperatures, it is not frost-hardy and should be protected during winter in colder climates.

Propagation and Maintenance

The plant can be easily propagated through stem cuttings or by division, as it has a natural tendency to root from the tips of its foliage as it spreads. To propagate from a cutting, snip a healthy section of stem and place it on a moist substrate like sphagnum moss. Placing the cutting in a covered container helps to maintain high humidity, which encourages rooting. Open the container periodically to allow for air circulation and to check the moisture level. Division involves separating a clump of the moss, ensuring each section has roots, and replanting them.

Maintenance for Rainbow Moss is minimal and primarily involves trimming. It can be done to shape the plant or control its spread. Trimming the edges can encourage fuller, denser growth, which is desirable when it is grown as a groundcover or in a terrarium. Any dead or faded growth can also be pruned out as needed to keep the plant looking tidy.

Common Rainbow Moss Issues

If you notice the foliage becoming crispy and brown, it is a sign of low humidity or insufficient watering. To remedy this, increase the frequency of misting or move the plant to a more humid location, like a bathroom or a terrarium. You must also ensure the soil remains consistently moist.

A loss of the signature iridescent blue color is related to lighting conditions. Too much direct sunlight can wash out the color and scorch the leaves, while extremely low light may also cause the blue hue to fade. Finding a spot with bright, indirect light is the best way to maintain the plant’s vibrant sheen.

Sparse or leggy growth is an indication that the plant is not receiving enough light. In its effort to find more light, the plant will stretch, leading to longer, weaker stems with less dense foliage. Moving the plant to a location with more adequate, but still indirect, light will encourage more compact growth.