Moss companion planting combines moss with small, shade-tolerant plants to create a cohesive, miniature ecosystem, often within a terrarium or a shaded garden bed. This gardening style delivers a vibrant, lush aesthetic that mimics a forest floor and requires minimal maintenance once established. Success relies on selecting plants that share the specific high-humidity and low-light needs of bryophytes, ensuring all elements thrive together in a balanced environment.
Shared Environmental Needs for Moss and Companions
Selecting appropriate companion plants requires understanding the non-negotiable conditions moss requires to thrive. Mosses are non-vascular plants that absorb water and nutrients directly through their leaves, which necessitates consistently high ambient humidity, ideally above 70% to 80% for many common species. This reliance on atmospheric moisture means that any companion plant must also be a species that naturally occurs in damp, humid, and sheltered habitats, making tropical and temperate forest floor flora the best candidates.
The light requirement is another limiting factor, as moss evolved to flourish beneath a dense forest canopy. They require low to moderate indirect light, meaning direct, intense sunlight is detrimental as it rapidly desiccates the delicate plant tissue and can cause scorching. Companion plants must therefore be highly shade-tolerant, with a preference for bright, filtered light. Utilizing full-spectrum LED grow lights is a common practice to provide consistent, indirect illumination.
Mosses do not possess a true root system, instead anchoring themselves with fine structures called rhizoids. The substrate for a moss companion planting setup must be well-draining yet moisture-retentive, preventing the environment from becoming waterlogged, which can lead to root rot in vascular plants. Many mosses prefer a slightly acidic pH, often in the range of 5.0 to 5.5, which means companion plants should also tolerate this mildly acidic soil composition.
Recommended Plants for Moss Gardens and Terrariums
The best companions for moss are miniature plants whose natural habitat mirrors the cool, damp, and shaded conditions of a mossy forest floor. Small ferns are a classic choice, as their feathery fronds offer a textural contrast to the dense, carpeting moss.
Ferns and Ground Covers
The Lemon Button Fern (Nephrolepis cordifolia ‘Duffii’) is popular because its small size and preference for consistently moist soil and indirect light make it highly compatible. Similarly, the Fluffy Ruffles Fern (Nephrolepis exaltata ‘Fluffy Ruffles’) is a compact variety that thrives in the high humidity of a closed environment.
Creeping ground covers create a seamless, layered landscape and are excellent for filling space between moss patches or hardscape elements. Baby’s Tears (Soleirolia soleirolii) forms a dense, bright green mat that enjoys the perpetually moist soil conditions moss favors, although it may require occasional trimming. Selaginella, often called “Peacock Fern” or “Peacock Moss,” thrives in humid, low-light settings due to its iridescent, blue-green foliage. The creeping fig (Ficus pumila) is a fine-leafed vine that can be used as a ground cover or allowed to climb hardscape within a terrarium.
Miniature and Epiphytic Plants
Miniature and epiphytic plants introduce vertical interest and unique textures that can be mounted directly onto wood or rock features. Tiny Begonia species, such as Begonia prismatocarpa, are suitable for larger enclosures, requiring very high humidity and consistently wet substrate. Miniature orchids, like those from the Microgramma genus, are epiphytes that naturally grow on trees, making them excellent moss companions. The Strawberry Begonia (Saxifraga stolonifera), with its fuzzy leaves and trailing runners, is tolerant of low light and moist, well-drained soil.
Step-by-Step Planting and Long-Term Care
Establishing a thriving moss companion ecosystem requires attention to the construction of the environment, particularly regarding drainage and planting depth. The process begins with layering the substrate to ensure proper water management. Start with a drainage layer of small pebbles, leca, or gravel at the bottom of the container to prevent water from pooling around the plant roots. A thin layer of activated charcoal should be placed above the drainage layer to filter impurities and maintain the freshness of the contained air and water cycle, which is important in closed terrariums.
The main growing medium is then added, typically a mix of potting soil, peat moss, and perlite or vermiculite, designed to be moisture-retentive but airy enough. When planting companion plants, space them to accommodate their mature size and avoid placing large root balls too close to the moss. Vascular plants should be settled into the soil layer, while moss pieces should be pressed gently but firmly onto the surface of the soil or hardscape, ensuring good contact for the rhizoids to anchor.
Long-term care involves managing moisture and growth to maintain the balance of the miniature ecosystem. In closed environments, condensation on the glass indicates sufficient humidity, and only occasional misting with distilled or filtered water is necessary when the moss appears dull. Open moss gardens require more frequent, light watering to keep the moss and soil consistently damp without oversaturation. Companion plants may need periodic trimming to prevent them from shading the moss or outcompeting smaller elements.