A Terrarium Plant Arrangement Dome is a self-contained, glass-enclosed miniature ecosystem featuring small-scale plants, decorative substrate, and sometimes mosses, stones, or figurines. Housed under a clear dome or bell jar, these arrangements create high humidity and stable microclimates ideal for moisture-loving plants like ferns, fittonias, peperomias, and small tropicals. They require low to moderate light, minimal watering, and occasional ventilation to prevent mold. Terrarium domes are decorative, low-maintenance pieces that bring a lush, indoor garden aesthetic to desks, shelves, or tabletops.

Light

• Bright, indirect light is best. Place near an east- or north-facing window or a few feet back from a south- or west-facing window. Avoid direct midday sun; glass magnifies heat and can scorch plants.

Temperature & Humidity

• Keep between 60–75°F (15–24°C). Avoid cold drafts, heaters, and sudden temperature swings.

• Domes retain humidity; open the lid briefly once a week for ventilation if you notice excessive condensation. For open-top domes, mist lightly when the air feels dry.

Watering

• Water sparingly. Terrariums are a closed, humid environment and need much less water than potted plants.

• Check soil moisture: use a finger or a wooden skewer — if the top 1 inch (2–3 cm) is dry, give a small amount of water. For closed domes, watering every 4–8 weeks is common; open domes may need water every 1–3 weeks depending on plant mix and room conditions.

• Water at the soil level to avoid wetting leaves and causing rot. Stop watering if you see mold or persistent standing water — open the dome and let it dry before adjusting watering frequency.

Soil & Drainage

• Use a well-draining, loose mix suitable for terrariums (peat-free potting mix or a mix with orchid bark/perlite for drainage).

• Maintain a drainage layer: small stones or LECA at the bottom with a thin layer of activated charcoal to control odors and prevent bacterial growth. A screen or mesh between drainage and soil helps keep layers separate.

Plant Selection & Placement

• Choose small, slow-growing, humidity-loving plants: fittonia, peperomia prostrata, baby tears (Soleirolia), fittonia, mini ferns, small mosses, and small trailing plants.

• Group plants with similar light and moisture needs. Leave spacing for airflow and growth; trim to keep proportions.

Pruning & Maintenance

• Remove dead or yellowing leaves promptly to prevent rot.

• Trim leggy or overgrown stems to maintain shape and airflow.

• Remove algae or mold from glass with a soft cloth; use gloves when handling plants.

Pests & Problems

• Common pests: fungus gnats in overly wet soil, mealybugs, or scale. Isolate affected terrarium and treat with manual removal, rubbing alcohol on a cotton swab, or a gentle insecticidal soap.

• Mold: reduce watering and increase ventilation. Remove moldy material and exposed soil surface.

• Leaf scorch: move to lower light and reduce temperature/heat exposure.

Fertilizing

• Fertilize sparingly — terrarium plants grow slowly and benefit from little to no regular feeding. If needed, use a diluted, balanced liquid fertilizer at 1/4 strength once or twice during the growing season.

Seasonal Notes

• Growth will slow in cooler months; reduce watering accordingly.

• Check more frequently in summer for signs of drying or overheating.

Quick Troubleshooting

• Excess condensation: open dome and air out, reduce watering, move to slightly lower light.

• No condensation & dry soil: increase ventilation but water lightly and check light (may be too bright and drying).

• Yellow leaves: overwatering or poor drainage — reduce water, remove affected leaves, check layers.

Enjoyment Tips

• Keep a small pair of scissors and a spray bottle nearby for quick maintenance.

• Rotate dome occasionally for even light exposure and balanced growth.