DIY Terrarium Soil Layer Estimator
Calculate the perfect soil layer depths for your terrarium based on container size and plant type.
Recommended Terrarium Supplies
Premium Terrarium Soil Blend
Specially formulated lightweight mix with perfect water retention for enclosed environments.
Get Mother Earth MixHorticultural Charcoal
Purifies terrarium air and prevents odors in closed systems.
View Espoma CharcoalFrequently Asked Questions
Terrarium layers serve specific purposes: drainage prevents waterlogging, charcoal purifies the environment, the barrier keeps soil from settling into drainage, and the soil layer provides nutrients. Each layer contributes to a healthy miniature ecosystem.
While possible, charcoal is highly recommended as it absorbs impurities, prevents odors, and reduces fungal growth. In closed terrariums especially, charcoal significantly improves long-term viability.
In well-balanced terrariums, soil can last 2-3 years. Replace when plants show nutrient deficiency, if mold appears, or when refreshing plantings. For open terrariums, top up soil annually as it compacts.