When to Plant Kohlrabi in Melbourne — Cool Temperate Guide

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

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

S = Seed Tray   T = Transplant   D = Direct Sow

Current Growing Conditions

Soil temperature: 21.9°C (optimal range: 10–30°C) ✓ Ready to plant

How to Grow Kohlrabi in Cool Temperate Australia

When to Plant

August to April. Long growing season. Spring, summer, and autumn all work. Avoid mid-winter sowing (too cold for germination).

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

Cool Temperate Growing Tips for Kohlrabi

Recommended Varieties

  • White Vienna
  • Purple Vienna
  • Kolibri F1
  • Superschmelz (giant variety - up to 4kg)

Key Challenges

  • Slugs in wet weather
  • Caterpillars
  • Club root

Pro Tips

  • Melbourne's cool climate is ideal for kohlrabi
  • Superschmelz is a novelty giant variety that stays tender even at 4kg
  • Can be sown almost year-round except June-July

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.

Common Kohlrabi Pests in Cool Temperate Zones

Fungal Soft Rot — Risk: LOW (score: 34/100)

Organic prevention: Net crops immediately after planting or sowing. Interplant with strong-scented herbs. Inspect leaf undersides for eggs every few days.

View all pest alerts →

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