Mature size & growth rate

How big does Walker's Low Catmint (Nepeta × faassenii 'Walker's Low') get?

Also called Walker's Low Catmint, Faassen's Catmint.

More about walker's low catmint

About Walker's Low Catmint

Nepeta × faassenii 'Walker's Low' · also called Walker's Low Catmint, Faassen's Catmint · flowering

Walker's Low Catmint is an RHS Award of Garden Merit winner prized for its long season of lavender-blue flower spikes and aromatic grey-green foliage. A tough, drought-tolerant perennial, it billows attractively at border edges. Cut back hard after the first summer flush to trigger prolific rebloom through autumn.

Mature size: 50–60 cm tall, 60–90 cm wide

Watch for — Flopping after first bloom: Stems sprawl after peak flowering in early summer. Cut the whole plant back to 10–15 cm immediately after bloom to stimulate fresh, upright regrowth and a strong second flush.

Indoor size vs how big it gets in the wild

Walker's Low Catmint 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 50–60 cm tall, 60–90 cm wide. 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

Walker's Low Catmint is a fast grower. Realistically, expect two to four years from a young plant to a room-filling specimen in good light. Its feeding profile backs this up: rarely required. a light top-dressing of compost in spring is sufficient. heavy feeding causes lush, floppy growth. this plant thrives on neglect in lean conditions.

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

How to keep walker's low catmint smaller

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

Divide the clump every year or two — splitting walker's low catmint 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 walker's low catmint 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 walker's low catmint bigger or faster

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

When walker's low catmint outgrows the room (or the pot)

"Too big" usually arrives as one of these signs for walker's low catmint:

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

Walker's Low Catmint size — frequently asked questions

How big does walker's low catmint get?

Walker's Low Catmint reaches 50–60 cm tall, 60–90 cm wide 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 walker's low catmint slow or fast growing?

Walker's Low Catmint is a fast grower. Expect two to four years from a young plant to a room-filling specimen in good light. Walker's Low Catmint 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 walker's low catmint take to reach full size?

Roughly two to four years from a young plant to a room-filling specimen in good light. Light, pot size and feeding move that timeline more than anything else.

How do I keep walker's low catmint smaller?

Divide the clump every year or two — splitting walker's low catmint 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 walker's low catmint 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.