Repotting guide

When & how to repot 'Red Russian' Kale (Brassica napus var. pabularia 'Red Russian')

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

How to tell 'red russian' kale needs repotting

Repotting on a calendar is less reliable than reading the plant. For 'red russian' kale, watch for these signs:

Roots circling the bottom of the module or pot, or poking out of the drainage holes.
The seedling dries out within a day and growth has visibly stalled.
Roots are white and matted in a tight spiral when you tip the plant out.
It has outgrown its current container for the stage of the season — pot 'red russian' kale on before it becomes hard root-bound.

For the underlying biology of a pot-bound root system and why it stalls a plant, see our guide to spotting and fixing a root-bound plant.

How often to repot 'red russian' kale

Pot on seedlings as they grow; not a perennial repot. 'Red Russian' Kaleis grown for one season, so the question is really “how often to pot on” — keep moving it up before the roots circle. Open, spreading, non-heading kale with tender, flat, deeply lobed oak-leaf foliage on slender red-purple stems; forms a loose rosette and resprouts readily when leaves are cut..

What size pot to step 'red russian' kale up to

Pot 'red russian' kale on gradually — a seedling jumped straight into a huge pot sits in cold, wet, airless soil and stalls. Step up one or two sizes at a time as the roots fill each container, finishing in a large final pot or the ground. The aim is roots that never circle and never check.

Not sure of the exact diameter? Our pot size calculator takes the current pot and root spread and tells you the right next size — it deliberately recommends a single step up, never a big jump.

The best time of year to repot 'red russian' kale

Pot 'red russian' kale on through the active growing season, whenever roots fill the current container — there is no single date, just "before it becomes root-bound". Avoid potting on during a cold snap.

Step-by-step: repotting 'red russian' kale

Pot on before it is root-bound. Check 'red russian' kale regularly; move it up as soon as roots reach the edge of the cell or pot, not after they have circled.
Step up one or two sizes. Choose the next container up — not a giant one. Cold, wet, unused soil around a small root system stalls seedlings.
Knock it out gently. Support the stem, tip the pot, and ease the rootball out without breaking it. A little teasing of circled roots at the base is fine.
Pot into rich mix. Set it into fresh fertile, well-drained loam, ph 6.0-7.5 at the same depth (tomatoes are the exception — they can go deeper to root along the stem).
Water in and grow on. Water well, keep it in good light, and resume feeding once it is established and growing again.

Aftercare

Water 'red russian' kale in well and keep it in bright light; a freshly potted-on seedling can wilt for a day while roots settle, so do not overcompensate by drowning it. Do not fertilise for about 1 week — fresh mix already carries nutrients and feeding freshly disturbed roots scorches them.

The right soil mix for 'red russian' kale

'Red Russian' Kale wants fertile, well-drained loam, ph 6.0-7.5. As a napus-type kale it copes with a slightly wider pH range and lighter soils than oleracea kales, but still does best in moisture-retentive ground enriched with compost. Good drainage prevents winter rot. Always use fresh mix when you repot — reusing old, broken-down soil reintroduces the compaction and poor drainage you are repotting to fix.

Repotting 'red russian' kale — frequently asked questions

How often should you repot 'red russian' kale?

Pot on seedlings as they grow; not a perennial repot for 'red russian' kale. 'Red Russian' Kale is a seasonal crop, so you pot it on as a growing plant rather than repotting a perennial. Step seedlings up gradually into fertile, well-drained loam, ph 6.0-7.5 so the roots never circle the cell, ending in a large final container. A root-bound transplant stalls and never fully recovers.

What size pot does 'red russian' kale need?

When is the best time of year to repot 'red russian' kale?

Can you put 'red russian' kale straight into a much bigger pot?

No. Even a fast-growing 'red russian' kale should only go up one pot size at a time. A vastly oversized pot holds a reservoir of wet soil the roots cannot reach, which stays cold and soggy and rots the roots — the opposite of what you wanted.

Should you fertilise 'red russian' kale after repotting?

Not immediately. Wait about 1 week after repotting 'red russian' kale. Fresh mix already contains nutrients, and feeding freshly cut or disturbed roots burns them. Resume your normal feeding routine once you see new growth.