Mature size & growth rate

How big does 'Red Russian' Kale (Brassica napus var. pabularia 'Red Russian') get?

Also called Red Russian kale, Ragged Jack kale.

More about 'red russian' kale

About 'Red Russian' Kale

Brassica napus var. pabularia 'Red Russian' · also called Red Russian kale, Ragged Jack kale · edible

Red Russian is a tender, frilled, flat-leaved kale with grey-green oak-shaped leaves and purple-red stems and veins that intensify in cold. Botanically a Brassica napus type, it is milder and more delicate than curly kale, excellent as both baby leaf and mature greens. Very cold-hardy and quick to crop, it tolerates poorer soils than most brassicas.

Mature size: 45-60 cm tall and 45 cm wide

Indoor size vs how big it gets in the wild

'Red Russian' Kale 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 45-60 cm tall and 45 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

'Red Russian' Kale 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: moderate feeder. mix a balanced fertiliser into the bed before planting and side-dress with a nitrogen feed every 4-6 weeks during active growth. cut-and-come-again baby-leaf crops benefit from a liquid feed after each harvest.

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

How to keep 'red russian' kale smaller

You are not stuck with the maximum size. For 'red russian' kale specifically, these are the levers, in order of impact:

Divide the clump every year or two — splitting 'red russian' kale 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 'red russian' kale 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 'red russian' kale bigger or faster

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

When 'red russian' kale outgrows the room (or the pot)

"Too big" usually arrives as one of these signs for 'red russian' kale:

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 'red russian' kale repotting guide. If you want more of this plant instead of a bigger one, the 'red russian' kale propagation guide turns prunings into new plants.

'Red Russian' Kale size — frequently asked questions

How big does 'red russian' kale get?

'Red Russian' Kale reaches 45-60 cm tall and 45 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 'red russian' kale slow or fast growing?

'Red Russian' Kale is a fast grower. Expect two to four years from a young plant to a room-filling specimen in good light. 'Red Russian' Kale 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 'red russian' kale 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 'red russian' kale smaller?

Divide the clump every year or two — splitting 'red russian' kale 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 'red russian' kale 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.