How to grow Gai Lan in Australia
Gai lan, also called Chinese broccoli or kai lan, is a fast, leafy member of the cabbage family grown for its thick, tender flowering stems, leaves and buds. It is cut just before the flowers open and keeps sending up new shoots for weeks. Grow it in the cooler months like other brassicas, with rich soil and steady water.
📖 Our full guide: How to Grow Gai Lan in Australia
At a glance
When to sow by region
| Region | When to sow | Regional note |
|---|---|---|
| South East Queensland | March to September | |
| Northern Rivers NSW | March to September | |
| Sydney & Coastal NSW | March to September | |
| Melbourne & Victoria | March to September | Sow Mar to Sep. Prefers cool season; bolt-resistant in Melbourne winter. Extend vs SEQ. |
| Adelaide & SA | March to September | Mediterranean: sow Mar to Sept. Gai Lan (Chinese broccoli) prefers cool weather; avoid summer. |
| Perth & WA | March to September | Mediterranean: sow Mar to Sept. Gai Lan (Chinese broccoli) prefers cool weather; avoid summer. |
| Tasmania | August to March | Sow Aug to Mar. Late summer sowings give the best autumn crops. |
| Canberra & ACT | February to April, September and October | Sow Feb to Apr for autumn harvest, or Sep to Oct for spring. Winter soil too cold for germination. |
| North Queensland | May to September | Dry season May to Sep. Gai lan is cool-season brassica; sow in dry months. |
| Darwin & Top End | May to September | Dry season May to Sep. Gai lan is cool-season brassica; sow in dry months. |
Not to be confused with: Broccolini, a hybrid of gai lan and broccoli with smaller leaves and a larger head, and Bok Choy, a different Asian green grown for its leaves and stalks.
Where to plant
Grow gai lan in full sun or part shade in rich, moist, well-drained soil improved with compost. Before sowing, work in a complete fertiliser that is high in nitrogen and potassium. It is a cool-season crop; in hot weather it flowers quickly and the stems turn tough.
Gai lan is a brassica, so do not plant it where cabbages, broccoli or other brassicas grew in the last few years. That rotation helps keep clubroot, a soil disease worst in acidic soil, out of the bed. Lime acidic soil before planting.
- South East Queensland, the Northern Rivers, Sydney, Melbourne, Adelaide and Perth: sow from March to September. Avoid summer sowings.
- Canberra: sow from February to April for an autumn harvest, or in September and October for spring. Winter soil is too cold for germination.
- Hobart: sow from August to March. Late summer sowings give the best autumn crops.
- North Queensland and Darwin: sow in the dry season, May to September.
How to plant
- Sow seed in a shallow drill about 1 to 2 cm deep, in rows about 30 cm apart, or two seeds per cell in punnets.
- Water the seed in. Seedlings appear in about a week.
- Thin to about 20 to 30 cm apart for full-sized plants, or 10 to 15 cm for baby leaves.
- Transplant punnet seedlings once they have a few true leaves, and water them in well.
- Cover young plants with insect-proof mesh straight away to keep cabbage white butterflies off.
- Sow a new batch every few weeks for a steady supply.
Watering and feeding
Gai lan needs consistently moist soil for thick, tender stems. Water regularly in dry weather, and more often in pots, which dry out quickly. Plants that dry out flower early and turn stringy.
Feed with a liquid fertiliser high in nitrogen every couple of weeks once plants are growing strongly, to keep leafy growth coming.
Harvesting
Start cutting when the main flower stem has formed and the buds are showing but before the first white or yellow flowers open, usually about 8 to 10 weeks after sowing. Cut the stem with a knife, taking the top 15 to 20 cm with its leaves and buds. Side shoots then grow from below the cut, and the more you harvest, the more the plant produces. Baby leaves can be picked from about three weeks.
Gai lan is best eaten fresh. Keep cut stems in a bag in the fridge for a few days.
Growing in pots
Gai lan grows well in a pot or trough at least 25 cm wide, filled with quality potting mix. Water often, as pots dry out quickly, feed every couple of weeks with a liquid fertiliser, and cover the pot with insect mesh.
Using it
Steam or blanch whole stems and serve them with oyster sauce, or slice and stir-fry them with garlic and ginger. The leaves, stems and buds are all eaten. Peel thick stems if the skin is tough.
Varieties
- Kailaan (White Flower)
- Green Lance F1
Companion planting
Gai lan grows alongside other cool-season vegetables, and like all brassicas it benefits from plants that bring in predators of caterpillars and aphids.
Good companions
- Dill Its flowers bring in hoverflies and parasitic wasps, which prey on aphids and caterpillars.
- Onion A low, upright crop that grows in the same season and uses little space between the brassicas.
- Beetroot A cool-season root crop that shares the bed without competing for the same space above ground.
Keep apart
Avoid planting these close to gai lan.
- Strawberry Strawberries and brassicas are often kept apart in companion planting lists. The evidence is thin; the practical reason is that they need different soil and rotation.
- Tomato A summer crop with different needs and pests, usually kept in a separate bed and rotation.
Pests and diseases
Gai lan has the same pests as other brassicas. Caterpillars are the main problem in warmer months.
Pests to watch for
- Cabbage moth Holes in the leaves and green caterpillars underneath or in the heart. Insect mesh keeps the adults off.
- Aphids Clusters of small grey insects under the leaves and on the flower buds. Hose them off or squash them.
- Flea beetle Tiny holes peppering the leaves of young plants in warm, dry weather.
- Slugs Seedlings eaten, with slime trails, mostly in damp weather.
Diseases to watch for
Common questions
When do you harvest gai lan?
When the flower stem has formed and the buds show, but before the first flowers open, usually 8 to 10 weeks after sowing. Cut the top 15 to 20 cm and the plant sends up side shoots for more harvests.
Does gai lan regrow after cutting?
Yes. Side shoots grow from below the cut, and regular harvesting keeps them coming for several weeks.
Why is my gai lan flowering so fast?
Heat and dry soil make it bolt. Sow it in the cooler months, keep the soil evenly moist and harvest before the flowers open.
What is the difference between gai lan and broccolini?
Broccolini is a hybrid of gai lan and broccoli. It has smaller leaves and slightly larger heads, while gai lan has broad leaves and thick stems.
How do I stop caterpillars on gai lan?
Cover the plants with fine insect mesh from planting, so cabbage white butterflies and cabbage moths cannot lay eggs. Check under the leaves and pick off any caterpillars.
When should I plant gai lan?
From March to September in most regions. Canberra sows in late summer to autumn or spring, Hobart from August to March, and the tropics in the dry season.
Sources we checked: RHS: Chinese broccoli, grow your own; Gardening Australia: Asian greens.