Mature size & growth rate

How big does Nepeta 'Six Hills Giant' (Nepeta 'Six Hills Giant') get?

Also called Six Hills Giant catmint, tall catmint.

More about nepeta 'six hills giant'

About Nepeta 'Six Hills Giant'

Nepeta 'Six Hills Giant' · also called Six Hills Giant catmint, tall catmint · flowering

Nepeta 'Six Hills Giant' is a large, vigorous catmint forming billowing mounds of grey-green aromatic foliage smothered in long spikes of lavender-blue flowers from early summer. Exceptionally bee-friendly, drought-tolerant and easy, it is a classic for softening path edges and rose borders. A hard cut-back after the first flush triggers a strong second bloom into autumn.

Mature size: 75-90 cm tall, 60-90 cm wide.

Watch for — Mid-season collapse: The clump can splay open and look tired after the first flush. Shear hard by a third to a half to trigger fresh growth and a second bloom.

Indoor size vs how big it gets in the wild

Nepeta 'Six Hills Giant' 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 75-90 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

Nepeta 'Six Hills Giant' 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: needs very little. skip feeding in average soil; a thin spring mulch is enough on poor ground. feeding rich soils produces weak, flopping stems and fewer flowers.

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

How to keep nepeta 'six hills giant' smaller

You are not stuck with the maximum size. For nepeta 'six hills giant' specifically, these are the levers, in order of impact:

Divide the clump every year or two — splitting nepeta 'six hills giant' 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 nepeta 'six hills giant' 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 nepeta 'six hills giant' bigger or faster

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

When nepeta 'six hills giant' outgrows the room (or the pot)

"Too big" usually arrives as one of these signs for nepeta 'six hills giant':

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 nepeta 'six hills giant' repotting guide. If you want more of this plant instead of a bigger one, the nepeta 'six hills giant' propagation guide turns prunings into new plants.

Nepeta 'Six Hills Giant' size — frequently asked questions

How big does nepeta 'six hills giant' get?

Nepeta 'Six Hills Giant' reaches 75-90 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 nepeta 'six hills giant' slow or fast growing?

Nepeta 'Six Hills Giant' is a fast grower. Expect two to four years from a young plant to a room-filling specimen in good light. Nepeta 'Six Hills Giant' 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 nepeta 'six hills giant' 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 nepeta 'six hills giant' smaller?

Divide the clump every year or two — splitting nepeta 'six hills giant' 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 nepeta 'six hills giant' 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.