How to grow Wombok in New Zealand
Wombok, also called Chinese cabbage, napa cabbage or wong bok, forms tight, pale, barrel-shaped heads with a mild, sweet flavour, essential for kimchi, stir-fries, dumplings and slaws. It bolts quickly in warm weather and long days, so in most of New Zealand it is sown from late summer into autumn, with a short spring window. Give it rich soil, steady water and room to form a full head.
📖 Our full guide: How to Grow Wombok in New Zealand
At a glance
When to sow by region
| Region | When to sow | Regional note |
|---|---|---|
| Northland | February to April, August to October | |
| Auckland | February to April, August to October | |
| Waikato & Bay of Plenty | February to April, August to October | |
| Central North Island | February to April, September and October | Skip August in the central North Island. Plant from September and cover young plants on frosty nights. |
| Wellington & Lower North Island | February to April, August to October | |
| Nelson & Marlborough | February to April, August to October | |
| Canterbury | February and March, August to November | Sow Aug to Nov and Feb to Mar. Cover early sowings with a cloche or frost cloth, as frosts run to mid October. Get the last sowing in by Mar so it sizes up before winter growth stops. |
| Otago & Southland | October to February | Start spring sowings in Oct under a cloche or frost cloth, as frosts run to late October. Cool summers let you keep sowing through Nov to Jan. Make the last sowing in Feb so the crop is ready before winter growth stops. |
| Central Otago | November to January | Sow from November to January, after the frosts. Earlier spring sowings bolt in the cold, and a late January sowing still heads up before the autumn frosts. |
Not to be confused with: Bok choy, which forms loose, upright heads with white stems, and round European cabbage.
Where to plant
Grow wombok in full sun in rich, well-drained soil that holds moisture, with room for each plant to form a full head. It needs more space and more consistent moisture than the smaller leafy Asian greens. Rotate it with non-brassica crops, as it shares clubroot and pests with other cabbages.
- Northland, Auckland, Waikato and the Bay of Plenty: sow from late summer through autumn for winter heads, and again in late winter to early spring.
- Central North Island: skip August; plant from September and cover young plants on frosty nights.
- Canterbury: sow from August to November and in February and March, covering early sowings with a cloche or frost cloth.
- Otago and Southland: start spring sowings in October under a cloche; cool summers let you keep sowing to January, with the last sowing in February.
- Central Otago: sow from November to January, after the frosts. Earlier spring sowings bolt in the cold, and a late January sowing still heads up before the autumn frosts.
Choosing a variety
- Barrel-headed napa types form tall, dense heads for kimchi and stir-fries.
- Look for slow-bolting varieties for spring sowings.
How to plant
- Dig in compost and sheep pellets or a vegetable fertiliser before planting.
- Sow seed in trays or direct, or plant seedlings at the depth they grew in the punnet. Wombok dislikes root disturbance, so transplant young.
- Space plants about 40 to 45 cm apart.
- Water in well and mulch lightly.
Watering and feeding
Keep the soil evenly moist but never waterlogged; dry soil makes the leaves tough and bitter and triggers bolting. Water at the base rather than over the leaves, and mulch lightly to hold moisture. Work a vegetable fertiliser into the soil before planting and side dress lightly if growth slows or leaves look pale. Avoid heavy nitrogen close to harvest, which makes leaves soft and more attractive to pests.
Pruning and care through the year
- Keep the water steady; a check from drought or cold often makes wombok bolt instead of heading.
- Cover young plants with fine insect netting during white butterfly season.
- Watch for slugs and snails, which hide in the heads in damp weather.
Harvesting
Wombok needs to form a full, firm head before harvesting, usually 10 to 12 weeks after planting. Cut the head at the base with a sharp knife. Harvest before it starts to elongate and bolt. Heads keep for a week or more in the fridge, and much longer as kimchi.
Companion planting
Wombok shares pests with other brassicas, so neighbours from other families help.
Good companions
- Onion From a different family and takes little space.
- Dill Its flowers draw hoverflies and tiny wasps that attack aphids and caterpillars.
- Beetroot A slim root crop that shares the bed.
Keep apart
Avoid planting these close to wombok.
- Strawberry Traditionally kept apart, and the big heads shade low strawberries.
- Tomato A summer crop with different timing and needs.
Pests and diseases
As brassicas, Asian greens share cabbage pests. Slugs and snails are the main problem in damp autumn and winter weather.
Pests to watch for
- Slugs and snails (slugs and snails) Ragged holes and missing seedlings, especially in damp weather. Check in the evening and after rain.
- White butterfly Green caterpillars and holes in leaves from spring to autumn. Cover young crops with fine insect netting.
- Aphids Clusters of grey-green insects on new growth and under leaves.
- Slugs
Diseases to watch for
- Clubroot Wilting plants with swollen, distorted roots. Rotate brassicas and lime acid soil.
- Black rot Yellow, V-shaped patches at the leaf edges with blackened veins.
- Downy mildew Yellow patches on leaves with grey growth beneath in cool, damp weather.
Common questions
Why does my wombok bolt instead of forming a head?
Warm weather, long days, cold shocks in spring and dry soil all trigger bolting. Sow from late summer into autumn in most areas, keep the soil evenly moist, and choose slow-bolting varieties for spring.
Is wombok the same as Chinese cabbage?
Yes. Wombok, wong bok, Chinese cabbage and napa cabbage are names for the same vegetable.
How long does wombok take to grow?
About 10 to 12 weeks from planting to a full, firm head.
When should I plant wombok in New Zealand?
Mostly from late summer to autumn, with a shorter window in early spring. In Central Otago, sow from November to January. Choose your region at the top of the page.
How do I stop caterpillars eating my wombok?
Cover young plants with fine insect netting during white butterfly season, from spring to autumn, and check the undersides of leaves regularly.
Sources we checked: Daltons: How to grow Asian greens; Yates NZ: How to grow Asian greens.