The spider plant, Chlorophytum comosum, is a durable and adaptable houseplant often chosen for its variegated foliage and ease of care. Although not a typical choice for the smallest enclosed spaces, it can be successfully grown in a terrarium setting. Success depends on using a container large enough to accommodate its eventual size and managing its robust growth habits.
Suitability for Enclosed Environments
The spider plant is a reasonable candidate for a terrarium due to its tolerance for a range of conditions, including the higher humidity levels characteristic of closed systems. It can thrive in saturated air without suffering the mold or fungal issues that plague less tolerant species. It also adapts well to the bright, indirect light optimal for terrariums, though consistent light exposure ensures the most vibrant variegation.
A significant consideration is the plant’s robust growth and mature size, averaging 1 to 2 feet tall and wide. It develops fleshy, tuberous roots to store water, which can quickly fill a small container. For this reason, spider plants are best suited for larger, open-style terrariums or those with semi-open lids that allow for easier maintenance. If planted in a smaller, fully closed vessel, its size necessitates frequent maintenance to prevent it from becoming root-bound and crowding out other plants.
Constructing the Terrarium Setup
Building a healthy terrarium requires a foundational layering system to manage moisture, since the glass container lacks drainage holes. The initial layer should be a 1- to 2-inch bed of pebbles or gravel, serving as a false bottom to collect excess water away from the roots. Above this, apply a thin layer of activated horticultural charcoal to filter impurities and neutralize odors that build up in a closed environment.
A barrier of mesh or sphagnum moss should then be placed over the charcoal to prevent the subsequent soil layer from migrating down and clogging the drainage layer. The planting medium itself should be a well-draining, general-purpose potting mix, possibly blended with perlite to ensure lightness and prevent compaction. When planting the spider plant, gently loosen the roots and position the plant in the center of the container, ensuring the crown rests slightly above the soil line to prevent rot.
Specialized Maintenance and Monitoring
Ongoing care for a spider plant within a terrarium differs from standard houseplant maintenance due to the enclosed environment’s self-regulating nature. Watering is the most delicate aspect and must be done sparingly, often only every few weeks or months, depending on the seal. The primary indicator for watering is condensation: persistently foggy glass means too much moisture, while no condensation means a small amount of water should be added.
Overwatering is the leading cause of plant failure in terrariums, resulting in root rot and fungal growth. When water is needed, apply it precisely with a syringe or narrow-spout bottle, targeting the soil base rather than misting the foliage. The terrarium should receive bright, indirect light, as direct sun can intensify the heat inside the glass and scorch the leaves. To prevent excessive moisture buildup, occasionally open the lid for a few hours to allow for brief ventilation and the release of excess humidity.
Managing Rapid Growth and Runners
The spider plant’s production of plantlets, or “spiderettes,” poses a unique challenge within the confines of a terrarium. To prevent the plant from quickly dominating the miniature landscape, frequent pruning of the foliage is necessary to maintain a manageable scale. Leaves should be trimmed at the base near the soil line to control the plant’s overall size and shape.
Mature spider plants send out long, arching stems that bear small, new plantlets. For a terrarium, it is better to plant one of these small, newly formed spiderettes rather than a mature plant, as this slows the initial growth phase. Once the plant begins producing runners, they can be snipped off at the base of the stem to redirect energy toward leaf development, or they can be propagated outside the terrarium.