When to Plant Kohlrabi in Brisbane, Subtropical Guide

Sow March to August. Right now in September it is out of season. The next sowing month is March.

Published · Last reviewed · By Garden Buddy
Growing advice is reviewed by hand. Planting dates, current conditions and prices on this page update daily.

This Kohlrabi guide is written for the Subtropical zone, which takes in Brisbane, the Gold Coast and the Sunshine Coast. Somewhere else? Your postcode picks the right one.

Not your zone? Cairns Sydney Melbourne Canberra Alice Springs Perth

Also handy: will it frost this week? and what grows in shade.

Kohlrabi

Photo: Wikimedia Commons

Kohlrabi is technically not a root vegetable. The edible part is a swollen stem that forms above ground. Fast-growing (55-70 days), mild-flavoured, and versatile in the kitchen, kohlrabi is an underused gem in Australian gardens. It thrives in cool weather, handles light frost, and is one of the best brassicas for beginners. Both the bulb and leaves are edible.

Planting Calendar for Subtropical

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
- - S/D S/T/D S/T/D S/T/D T/D T/D - - - -

S = Seed Tray   T = Transplant   D = Direct Sow

Want a nudge when it is Kohlrabi sowing time in Brisbane?

One email a week with what is worth planting in the Subtropical zone right now, Kohlrabi included, plus which veg has jumped in price at the supermarket. Free, and you can stop it in one click.

Current Growing Conditions

Soil temperature: 20.4°C (optimal range: 10–30°C) ✓ Ready to plant

That figure is read off my own weather station here at Dayboro in South East Queensland at 18:55 yesterday, not a model. The radar, the rain gauge and the forecasts behind it sit on Dayboro.au.

How to Grow Kohlrabi in Subtropical Australia

When to Plant

February to August. Autumn and winter are the prime growing season. Spring sowings bolt in October heat.

Soil
Rich, well-drained soil with plenty of organic matter. Prefers neutral to slightly alkaline soil. Dig in compost and well-rotted manure before planting. Add lime to acidic soils (critical for preventing clubroot).
pH Range
6.5-7.5
Sunlight
Full sun (6+ hours). Tolerates light shade, especially in warmer zones where afternoon shade prevents bolting.
Spacing
20cm apart, 35cm between rows
Watering
Consistent, even moisture throughout growth. Water deeply 2-3 times per week. Inconsistent watering causes the stem bulb to become woody and split. Drip irrigation preferred.

Companion plants: Beetroot, Celery, Cucumber, Dill, Lettuce, Onion

Avoid planting near: Strawberry, Tomato, Runner Bean

Subtropical Growing Tips for Kohlrabi

Recommended Varieties

  • White Vienna
  • Purple Vienna
  • Kolibri F1

Key Challenges

  • Bolting in warm weather
  • Cabbage white butterfly year-round
  • Humidity-driven diseases

Pro Tips

  • SEQ gardeners: autumn-winter is your window, February to July
  • Succession sow every 2-3 weeks for continuous harvest
  • Purple Vienna is more heat-tolerant than White Vienna

Harvesting Kohlrabi

When ready: Stem bulb is 6-8cm diameter (tennis ball size) for standard varieties. Bulb should feel firm and smooth. Harvest promptly. Overgrown bulbs (>10cm for standard varieties) become woody and fibrous. Exception: Superschmelz stays tender up to 20cm.

How to harvest: Cut stem just below the bulb with a sharp knife, or pull the entire plant. Trim off leaves (save for cooking, they are edible). Trim the root.

Where to next

What kohlrabi costs in the shops right now, retailer by retailer, updated daily.

Also worth sowing in the subtropical zone this September: Lemongrass, Ginger, Beetroot and Chilli Peppers.

The pest most likely to find your kohlrabi: Cabbage White Butterfly.

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Common Questions About Kohlrabi

When do you plant kohlrabi in Australia?

It depends on your climate zone, not the calendar month alone. Planting months by zone:

Does kohlrabi grow all year round in Brisbane?

No. In the Subtropical zone the planting months are Mar to Aug. Outside that window it either bolts, sulks or gets cut down by the weather.

Which zone am I in?

Type your postcode into the box under the heading and the page tells you, and links this crop in your own zone if it differs. Or look it up on the grow zone map. This page is the Subtropical zone, Brisbane is its reference city.