Mature size & growth rate

How big does Nun's Orchid (Phaius tankervilleae) get?

Also called Swamp Orchid, Veiled Nun Orchid.

More about nun's orchid

About Nun's Orchid

Phaius tankervilleae · also called Swamp Orchid, Veiled Nun Orchid · flowering

Phaius tankervilleae is a robust terrestrial orchid from Asia and the Pacific, sending up tall spikes of large, reddish-brown flowers backed with white and a rosy, trumpet-shaped lip. Unlike epiphytic orchids it grows in rich, moisture-retentive soil, wanting bright shade, warmth, steady water and feeding in growth, and is among the easiest orchids to grow as a houseplant or shaded garden plant.

Mature size: Foliage 60-90 cm tall and arching; flower spikes can reach 0.9-1.2 m, each carrying numerous flowers up to about 10-12 cm across. Forms a substantial clump over time.

Watch for — Failure to flower: Often too little light, insufficient feeding, or an immature clump. Brighten the position, feed through growth, and let the plant build several mature pseudobulbs.

Indoor size vs how big it gets in the wild

Nun's Orchid 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 foliage 60-90 cm tall and arching. In the ground with no restriction it is a completely different plant — flower spikes can reach 0.9-1.2 m, each carrying numerous flowers up to about 10-12 cm across. forms a substantial clump over time. — 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

Nun's Orchid is a moderate grower. Realistically, expect three to six years to reach mature indoor size, gaining a steady amount each growing season. Its feeding profile backs this up: feed regularly during active growth and spiking with a balanced fertiliser at half strength every one to two weeks, as this vigorous terrestrial is a relatively heavy feeder. reduce feeding after flowering and during the cooler, lower-light rest.

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

How to keep nun's orchid smaller

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

Divide the clump every year or two — splitting nun's orchid 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 nun's orchid 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 nun's orchid bigger or faster

If you want it to fill the space sooner, push the conditions rather than hoping — for nun's orchid 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 nun's orchid light requirements page covers exactly how bright a spot it needs to grow at its potential instead of stalling.

When nun's orchid outgrows the room (or the pot)

"Too big" usually arrives as one of these signs for nun's orchid:

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 nun's orchid repotting guide. If you want more of this plant instead of a bigger one, the nun's orchid propagation guide turns prunings into new plants.

Nun's Orchid size — frequently asked questions

How big does nun's orchid get?

Nun's Orchid reaches foliage 60-90 cm tall and arching when grown indoors, and far larger where it grows unrestricted (flower spikes can reach 0.9-1.2 m, each carrying numerous flowers up to about 10-12 cm across. forms a substantial clump over time.). 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 nun's orchid slow or fast growing?

Nun's Orchid is a moderate grower. Expect three to six years to reach mature indoor size, gaining a steady amount each growing season. Nun's Orchid 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 nun's orchid take to reach full size?

Roughly three to six years to reach mature indoor size, gaining a steady amount each growing season. Light, pot size and feeding move that timeline more than anything else.

How do I keep nun's orchid smaller?

Divide the clump every year or two — splitting nun's orchid 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 nun's orchid 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.