Ferns are ideal for closed terrariums due to their love for high humidity and consistent moisture. Here are some of the best fern species for a closed terrarium:

Maidenhair Fern (Adiantum spp.):

Features: Maidenhair ferns have delicate, fan-shaped fronds that grow on wiry black stems. Their light, airy appearance adds a soft, ethereal quality to any terrarium.
Care: These ferns thrive in high humidity and indirect light. Keep the soil consistently moist but avoid waterlogging.

Boston Fern (Nephrolepis exaltata):

Features: Lush, feathery fronds that grow in a dense, bushy manner.
Care: Thrives in bright, indirect light and high humidity. Requires regular misting to keep the fronds healthy.

Bird’s Nest Fern (Asplenium nidus):

Features: Broad, wavy fronds that emerge from a central rosette, resembling a bird’s nest.
Care: Prefers indirect light and high humidity. Water the soil directly rather than the rosette to avoid rot.

Button Fern (Pellaea rotundifolia):

Features: Small, round leaflets along thin, wiry stems.
Care: Does well in low to medium light and high humidity. Keep the soil evenly moist.

Lemon Button Fern (Nephrolepis cordifolia ‘Duffii’):

Features: Small, rounded leaflets with a subtle lemon scent.
Care: Prefers bright, indirect light and high humidity. Keep the soil moist but allow the top layer to dry out slightly between waterings.

Kangaroo Paw Fern (Microsorum diversifolium):

Features: Glossy, dark green fronds with a distinctive, leathery texture.
Care: Thrives in medium to low light and high humidity. Regular watering is necessary to keep the soil moist.

Cretan Brake Fern (Pteris cretica):

Features: Variegated fronds with white or silvery stripes along the midrib.
Care: Prefers bright, indirect light and high humidity. Maintain consistent moisture in the soil.

Silver Brake Fern (Pteris ensiformis):

Features: Striking fronds with silvery-white stripes.
Care: Needs bright, indirect light and high humidity. Keep the soil moist but ensure good drainage.

Japanese Holly Fern (Cyrtomium falcatum):

Features: Dark green, holly-like fronds that are leathery and robust.
Care: Prefers medium light and high humidity. Water regularly to keep the soil consistently moist.

Heart Fern (Hemionitis arifolia):

Features: Heart-shaped leaves with a shiny, dark green appearance.
Care: Thrives in low to medium light and high humidity. Ensure the soil remains moist at all times.

Tips for Growing Ferns in a Closed Terrarium

Maintain High Humidity:

Closed terrariums naturally retain moisture, creating a humid environment ideal for ferns. Mist the terrarium regularly if necessary opening the terrarium will also help with air circulation and prevent mould growth.. Keep the soil consistently moist but avoid waterlogging. Use a well-draining substrate to prevent root rot.

Ferns prefer indirect light. Place the terrarium near a window with filtered light or use artificial grow lights. Remove dead or yellowing fronds to keep the terrarium looking neat and to prevent decay.
By choosing the right fern species and providing proper care, you can create a lush, green oasis in your closed terrarium.

Regular Pruning:

Remove dead or yellowing fronds to keep the terrarium looking neat and to prevent decay.
By choosing the right fern species and providing proper care, you can create a lush, green oasis in your closed terrarium.