How to grow Fennel in Australia

Where to plant

Grow herb fennel in a warm, sunny, sheltered spot in light, free-draining soil. It dislikes waterlogged ground. Once established it forms a clump of stems up to 2 m tall that copes with dry spells, and in cold areas it dies back in winter and regrows from the base in spring. Give it room, and its own spot away from other crops.

Weeds come first with fennel. Wild fennel has naturalised along roadsides, railways, drains, waterways and in grassland and woodland across the coastal south and south east, especially in Victoria, eastern New South Wales, Tasmania and the ACT, where it forms dense stands. In Tasmania, fennel is a declared weed and its sale is prohibited, and in several Victorian regions it is a regionally controlled weed. Check your state's weed rules before planting, and never let plants drop seed near bushland or waterways.

• South East Queensland, the Northern Rivers, Sydney, Adelaide and Perth: sow from March to August.
• Melbourne and Canberra: sow from March to August. Cool weather delays flowering. Keep seed heads cut, as wild fennel is a problem weed around both cities.
• Hobart and the rest of Tasmania: fennel is a declared weed in Tasmania, so do not plant herb fennel there. Grow dill or chervil for a similar flavour instead.
• North Queensland and Darwin: sow in the dry season, May to August.

Choosing a variety

Common green herb fennel and bronze fennel, which has smoky purple-bronze leaves, are grown the same way. Both are grown for leaves and seed, not for a bulb. If you want the bulb, grow Florence fennel instead.

How to plant

1. Sow seed direct where the plant is to grow, about 1 cm deep. Fennel has a long taproot and does not like being moved.
2. Keep the soil moist until seedlings appear, usually in about 10 days.
3. Thin seedlings to at least 30 cm apart.
4. Water regularly while plants are young. Once established they need little care.

Watering and feeding

Water young plants regularly until they establish. Mature clumps tolerate dry spells and need only an occasional deep watering in long, hot dry periods. Never leave the roots in soggy soil.

Fennel needs little or no feeding and grows best in average soil. Rich soil and heavy feeding give soft, floppy stems.

Pruning and care through the year

• Cut off the flower heads as soon as they fade, before the seed ripens and drops, unless you are collecting seed. If you collect seed, cut the heads as soon as the seed turns brown and dry them indoors.
• Pull up self-sown seedlings while they are small; older plants have deep taproots that are hard to remove.
• In cool areas, cut the old stems back to the base in late autumn or winter once they die down.
• Keep fennel away from dill if you save seed, as the two can cross.
• Never put seed heads in green waste or compost that will be spread elsewhere.

Harvesting

Snip young leaves as you need them once the plant is growing strongly, usually 2 to 3 months after sowing. Regular cutting gives a steady supply of fresh, tender growth. The leaves wilt quickly, so pick just before using.

For seed, let a few flower heads ripen in late summer. Cut whole heads when the seeds turn from green to brown, dry them upside down in a paper bag, then rub out the seeds and store them in an airtight jar. The yellow flowers are edible too.

Growing in pots

A pot is a good way to contain herb fennel. Use a pot at least 30 cm deep for the taproot, with a free-draining potting mix, and keep it in full sun. Water when the top of the mix dries out, and still cut the flower heads before they set seed.

Using it

Use the feathery leaves with fish, in salads, potato dishes and dressings. The seeds go into bread, sausages, curries and tea. The flowers and the pollen are used as a garnish.