Mature size & growth rate

How big does Fairy Bells (Melasphaerula ramosa) get?

Also called Fairy bells, Fairy grass.

More about fairy bells

About Fairy Bells

Melasphaerula ramosa · also called Fairy bells, Fairy grass · flowering

Melasphaerula ramosa is a slender cormous plant in the family Iridaceae, native to the Western Cape of South Africa where it grows in fynbos scrub and seasonally wet lowlands. The branched wiry stems carry numerous small creamy-white to pale yellow bell-shaped flowers with a faint musky scent in spring. It follows a Mediterranean growth cycle — actively growing through the cool, wet autumn and winter, then dying back completely in summer; in cooler climates it thrives as a cool-greenhouse or cold-frame subject. Toxicity to pets has not been formally assessed by the ASPCA; treat as mildly toxic as an Iridaceae corm plant.

Mature size: 30–50 cm tall, 10–20 cm spread.

Watch for — Aphids: Soft new growth in autumn may attract aphid colonies; treat early with an insecticidal soap spray, as heavy infestations weaken the slender stems and distort flowers.

Indoor size vs how big it gets in the wild

Fairy Bells 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 30–50 cm tall, 10–20 cm spread.. A pot, your light levels and a little pruning are what set the final size in a home, far more than the plant's theoretical potential.

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

Fairy Bells 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 with a balanced liquid fertiliser at half strength monthly during active growth from autumn to early spring; do not feed during summer dormancy.

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

How to keep fairy bells smaller

You are not stuck with the maximum size. For fairy bells specifically, these are the levers, in order of impact:

Divide the clump every year or two — splitting fairy bells 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 fairy bells 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 fairy bells bigger or faster

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

When fairy bells outgrows the room (or the pot)

"Too big" usually arrives as one of these signs for fairy bells:

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 fairy bells repotting guide. If you want more of this plant instead of a bigger one, the fairy bells propagation guide turns prunings into new plants.

Fairy Bells size — frequently asked questions

How big does fairy bells get?

Fairy Bells reaches 30–50 cm tall, 10–20 cm spread. when grown indoors. 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 fairy bells slow or fast growing?

Fairy Bells is a moderate grower. Expect three to six years to reach mature indoor size, gaining a steady amount each growing season. Fairy Bells 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 fairy bells 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 fairy bells smaller?

Divide the clump every year or two — splitting fairy bells 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 fairy bells 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.