Can You Put A Fern In A Terrarium

Yes, you can put a fern in a terrarium.
 
Ferns are one of the best plants for a terrarium because they love the humid, enclosed environment a glass container provides.
 
If you’re wondering whether you can put a fern in a terrarium, the short answer is absolutely yes, but there are a few things to consider before adding a fern to a terrarium.
 
The key is choosing the right fern species and setting up the terrarium so that your fern thrives inside it.
 
In this post, we’ll explore why putting a fern in a terrarium works so well, which ferns are best for terrariums, and how to care for your fern once it’s inside the terrarium.
 
Let’s dig in and get your terrarium fern-ready.
 

Why You Can Put a Fern in a Terrarium

Putting a fern in a terrarium is a natural match because ferns evolved in damp, shaded forest floors where humidity stays high and light is filtered.
 
A sealed or semi-sealed terrarium mimics those exact conditions perfectly.
 
Here’s why placing a fern in a terrarium works so well:

1. Terrariums Create the Humidity Ferns Crave

Ferns need consistent moisture in the air, and a terrarium traps that humidity beautifully.
 
When you put a fern in a terrarium, the glass walls prevent moisture from escaping, so the air stays damp around the fronds.
 
This high humidity is exactly what ferns require to keep their leaves from drying out and browning at the tips.
 
Without a terrarium, many ferns struggle in dry indoor air, but a terrarium solves that problem instantly.
 

2. Terrariums Provide Filtered Light That Ferns Love

Most ferns are understory plants that grow in dappled sunlight beneath taller trees.
 
When you place a fern in a terrarium, the glass naturally diffuses incoming light, creating the soft, indirect conditions ferns prefer.
 
Direct sunlight can scorch fern leaves, but a terrarium acts like a gentle filter, giving your fern exactly the right brightness.
 
So putting a fern in a terrarium protects it from harsh rays while still giving it enough light to grow.
 

3. Terrariums Keep the Soil Evenly Moist

Ferns dislike dry soil and also hate soggy roots, but a well-built terrarium maintains a perfect balance.
 
When you put a fern in a terrarium with a drainage layer of pebbles or charcoal, excess water collects below the soil while the top remains damp.
 
This steady moisture level is exactly what ferns need to stay lush and green without rotting.
 
For anyone who tends to forget watering, a closed terrarium with a fern can even become self-watering to a degree.
 

Best Ferns to Put in a Terrarium

Not every fern grows well inside a glass enclosure, so picking the right kind matters when you put a fern in a terrarium.
 
Compact, slow-growing fern species are ideal because they won’t outgrow their space quickly.
 
Here are the top ferns to consider for your terrarium:

1. Maidenhair Fern (Adiantum)

Maidenhair ferns have delicate, fan-shaped leaves that look magical inside a terrarium.
 
They need very high humidity, which a closed terrarium provides perfectly.
 
When you put a maidenhair fern in a terrarium, its fronds will stay soft and green, but without that humidity it quickly turns crispy.
 
This fern thrives in a terrarium and adds a graceful, airy texture to your mini garden.
 

2. Button Fern (Pellaea rotundifolia)

Button ferns are compact and produce round, button-like leaflets along thin stems.
 
They stay small, making them excellent for small or medium-sized terrariums.
 
Putting a button fern in a terrarium is a great choice if you want a fern that tolerates slightly lower humidity than other species.
 
It still loves the moisture but adapts better if you leave the lid off occasionally.
 

3. Bird’s Nest Fern (Asplenium nidus)

Bird’s nest ferns have broad, wavy, bright green leaves that form a rosette shape.
 
They are a bit larger but work well in open or wide terrariums where they have room to spread.
 
When you put a bird’s nest fern in a terrarium, avoid burying the center crown, as that can cause rot.
 
Its bold foliage contrasts nicely with smaller ferns and mosses.
 

4. Lemon Button Fern (Nephrolepis cordifolia ‘Duffii’)

A more compact cousin of the Boston fern, the lemon button fern has tiny rounded leaflets and a pleasant lemony scent.
 
It stays petite and dense, ideal for terrariums where you want a full look without overgrowth.
 
Putting a lemon button fern in a terrarium is low-maintenance and forgiving of occasional drying out.
 

How to Care for a Fern in a Terrarium

Once you put a fern in a terrarium, a little routine care keeps it thriving for months or even years.
 
Follow these simple steps to make sure your fern stays happy inside the glass:

1. Water Sparingly and Check the Soil

Terrariums recycle moisture, so you will water far less than a potted plant.
 
Before watering your fern in a terrarium, stick your finger in the soil, and if it feels damp, skip watering.
 
Only add water when the top inch of soil feels dry, and use a spray bottle or small watering can to avoid flooding.
 
Overwatering can lead to mold or root rot, so err on the side of dryness with a closed terrarium.
 

2. Provide Bright, Indirect Light

Place your terrarium near a north or east-facing window where it gets plenty of indirect sunlight.
 
If the leaves of your fern start looking pale or stretched, it needs more light.
 
If they turn yellow or brown at the edges, the light may be too strong.
 
Rotating the terrarium every week helps the fern grow evenly.
 

3. Prune Yellow or Dead Fronds

Even healthy ferns occasionally lose older fronds.
 
When you put a fern in a terrarium, check it monthly and snip off any yellow or brown leaves at the base.
 
This keeps moisture from building up on dead material and prevents fungal problems.
 
It also lets fresh fronds grow in, keeping your fern looking full and vibrant.
 

4. Open the Lid Occasionally

If your terrarium is fully sealed, it needs some fresh air exchange.
 
Open the lid for an hour every week or two to prevent mold from accumulating.
 
You can also remove the lid permanently if you notice condensation constantly dripping, which can be too wet for your fern.
 
A partially open top still provides high humidity while improving airflow.
 

So, Can You Put a Fern in a Terrarium?

Yes, you can put a fern in a terrarium, and it’s one of the best ways to grow these beautiful plants indoors.
 
Putting a fern in a terrarium creates a self-sustaining mini ecosystem that meets the fern’s need for humidity, filtered light, and steady moisture.
 
The key to success is choosing a compact fern species like maidenhair, button, or bird’s nest fern and setting up your terrarium with proper drainage and light.
 
Once you put a fern in a terrarium, basic care like infrequent watering, occasional pruning, and a little airflow keeps it lush for a long time.
 
So go ahead and add a fern to your terrarium, you’ll love watching it thrive inside its glass world.