Mature size & growth rate

How big does Bird's Nest Fern (Asplenium nidus) get?

Also called Bird's nest fern, Nest fern, Crow's nest fern.

More about bird's nest fern

About Bird's Nest Fern

Asplenium nidus · also called Bird's nest fern, Nest fern · tropical

The bird's nest fern is a tropical epiphytic fern grown for its glossy, strap-like fronds that unfurl in a rosette from a fuzzy central crown. Its one defining need is steady moisture without ever wetting that crown: water the soil around the rim, keep the compost evenly damp, and give it warm, humid, draught-free air in bright indirect light.

Mature size: Indoors typically 45-60 cm tall with fronds 30-60 cm long; in the wild fronds can reach 1.2 m or more.

Indoor size vs how big it gets in the wild

Bird's Nest Fern stays fairly low but widens over time — it spreads into a bigger clump by offsets, runners or rhizomes rather than shooting upward. Indoors and in a pot, expect typically 45-60 cm tall with fronds 30-60 cm long. In the ground with no restriction it is a completely different plant — in the wild fronds can reach 1.2 m or more. — which is why the pot, the light and the pruning matter so much for the size you actually end up with.

Size here is about width, not height: the plant builds an ever-wider clump or sends out plantlets and runners while staying relatively short.

Growth rate and years to mature

Bird's Nest Fern is a slow grower. Realistically, expect many years — it gains very little each season, so it can hold the same shelf-sized footprint for 5-10+ years. Its feeding profile backs this up: feed sparingly, only during active growth from late spring through summer. apply a balanced liquid houseplant fertiliser at half the recommended strength about once a month, and pour it onto the compost rather than over the fronds, which can spot or burn. no feeding is needed in autumn and winter when growth slows.

Want this turned into the right next pot at the right moment? The pot size calculator and the bird's nest fern repotting guide cover when and how much to size up — pot size is one of the biggest levers on how fast bird's nest fern grows.

How to keep bird's nest fern smaller

You are not stuck with the maximum size. For bird's nest fern specifically, these are the levers, in order of impact:

Divide the clump every year or two — splitting bird's nest fern is the main way to control its spread and refresh it.
Remove runners, plantlets or offsets as they appear if you want it to stay a single tight clump.
Keep it slightly pot-bound; a snug pot naturally limits how wide the clump can get.

The keep-it-smaller method, step by step

Lift the whole plant. Slide bird's nest fern out of its pot in spring when the clump has filled it.
Split the clump. Tease or cut the rootball into two or more sections, each with healthy roots and growth.
Repot one division. Put a single division back in the original pot to reset it to a smaller size; pot or give away the rest.
Remove offsets as they form. Through the year, detach new runners or pups to stop it spreading again.

How to grow bird's nest fern bigger or faster

If you want it to fill the space sooner, push the conditions rather than hoping — for bird's nest fern the accelerators are:

Give it a wider pot and let the clump fill it — width is exactly how this plant gets bigger.
Good light plus regular feeding maximises offset and runner production.
Leave plantlets and offsets attached and feed through the growing season for the fastest spread.

Light is almost always the ceiling. The bird's nest fern light requirements page covers exactly how bright a spot it needs to grow at its potential instead of stalling.

When bird's nest fern outgrows the room (or the pot)

"Too big" usually arrives as one of these signs for bird's nest fern:

The clump bulging over the pot rim or splitting the pot — the cue to divide, not to find a bigger room.
A dense centre that goes bare or tired while the edges keep spreading.
Runners or offsets escaping across the shelf or into neighbouring pots.

If it is the pot rather than the room, it is a repotting job, not a goodbye — see the bird's nest fern repotting guide. If you want more of this plant instead of a bigger one, the bird's nest fern propagation guide turns prunings into new plants.

Bird's Nest Fern size — frequently asked questions

How big does bird's nest fern get?

Bird's Nest Fern reaches typically 45-60 cm tall with fronds 30-60 cm long when grown indoors, and far larger where it grows unrestricted (in the wild fronds can reach 1.2 m or more.). Size here is about width, not height: the plant builds an ever-wider clump or sends out plantlets and runners while staying relatively short.

Is bird's nest fern slow or fast growing?

Bird's Nest Fern is a slow grower. Expect many years — it gains very little each season, so it can hold the same shelf-sized footprint for 5-10+ years. Bird's Nest Fern stays fairly low but widens over time — it spreads into a bigger clump by offsets, runners or rhizomes rather than shooting upward.

How long does bird's nest fern take to reach full size?

Roughly many years — it gains very little each season, so it can hold the same shelf-sized footprint for 5-10+ years. Light, pot size and feeding move that timeline more than anything else.

How do I keep bird's nest fern smaller?

Divide the clump every year or two — splitting bird's nest fern is the main way to control its spread and refresh it. Remove runners, plantlets or offsets as they appear if you want it to stay a single tight clump. Keep it slightly pot-bound; a snug pot naturally limits how wide the clump can get.

How can I make bird's nest fern grow bigger or faster?

Give it a wider pot and let the clump fill it — width is exactly how this plant gets bigger. Good light plus regular feeding maximises offset and runner production. Leave plantlets and offsets attached and feed through the growing season for the fastest spread.