When to Plant Fennel (herb) in Brisbane — Subtropical Guide

Fennel (herb)

Photo: Wikimedia Commons

Herb fennel (common fennel) is a tall, feathery perennial grown for its anise-flavoured leaves, stems and seeds. NOT the same as Florence/bulb fennel (F. vulgare var. azoricum). Herb fennel is hardy, drought-tolerant, and can become a large landscape plant reaching 1.5-2m. Considered a weed in parts of Australia - grow responsibly.

Current Growing Conditions

Soil temperature: 23.6°C (optimal range: 10–25°C) ✓ Ready to plant

How to Grow Fennel (herb) in Subtropical Australia

When to Plant

Sow almost year-round: best Feb-Nov. Perennial in this zone.

Soil
Any well-drained soil. Tolerant of poor soils. Drought tolerant once established.
pH Range
5.5-7.0
Sunlight
Full sun.
Spacing
30cm apart, 60cm between rows
Watering
Low water needs once established. Water regularly when young. Very drought tolerant as a perennial.

Companion plants: Dill (distant), Sage

Avoid planting near: Tomato, Bean, Capsicum, Coriander - fennel is allelopathic and inhibits growth of many vegetables

Subtropical Growing Tips for Fennel (herb)

Recommended Varieties

  • Common fennel
  • Bronze fennel
  • Sweet fennel

Key Challenges

  • Can become weedy - deadhead to prevent spread
  • Self-sows aggressively

Pro Tips

  • WARNING: Herb fennel is an environmental weed in parts of QLD and NSW. Deadhead religiously.
  • Bronze fennel is ornamental and equally useful culinarily
  • Keep away from vegetable garden due to allelopathic effects

Harvesting Fennel (herb)

When ready: Harvest leaves anytime once plant is established. Seeds ready when brown on plant.

How to harvest: Snip feathery fronds as needed. Cut seed heads when brown and dry in paper bags. Harvest young stems for cooking.

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