How to grow Celeriac in Australia

Where to plant

Grow celeriac in full sun or light shade in rich, moisture-retentive soil with plenty of compost. It is a thirsty plant and must never dry out; dry soil gives small, woody roots. Avoid beds where celery, celeriac, carrots or parsnips grew in the last few years, as they share diseases.

Young plants are sensitive to cold: a run of nights below about 10°C can make them bolt to flower later instead of forming a root. Do not plant seedlings out into cold weather.

• Melbourne: sow from January to June; early sowings in January and February give the best roots.
• Sydney, South East Queensland and the Northern Rivers: sow from February to May or June, in the cooler part of the year.
• Adelaide and Perth: sow from August to October or November and transplant about eight weeks later. Keep it constantly moist through summer; the roots swell in autumn.
• Hobart and Canberra: sow from September to November and transplant by December. Harvest from autumn into winter; frost improves the flavour.
• North Queensland and Darwin: not viable, as it needs a long cool season.

Choosing a variety

• Giant Prague is a long-established variety with large, smooth roots.
• Monarch is known for smooth roots with white flesh.

How to plant

1. Sow the tiny seed on the surface of a punnet of fine seed-raising mix and cover it with just a light sprinkling of mix. Keep it moist and warm, at about 15°C.
2. Seedlings are slow, taking two to three weeks to appear. Prick them out into small pots when they are big enough to handle.
3. Harden seedlings off and plant out about eight weeks after sowing, once nights are reliably mild, about 30 cm apart.
4. Plant with the crown sitting at soil level, not buried. Water in well and mulch.

Watering and feeding

Water often and deeply so the soil stays constantly moist through the whole season. Mulch thickly.

Feed regularly through the growing season with compost and a liquid fertiliser every few weeks to keep growth steady.

Pruning and care through the year

• As the plants grow, gradually remove the outer leaves as they fall flat, which exposes the crown and helps it swell.
• Remove any side shoots, and any leaves with dry patches or spots.
• Keep the bed weeded; celeriac is slow to establish and competes poorly.

Harvesting

Lift roots from about five to six months after sowing, once they are a good size. They can grow quite large without turning woody. In cool areas, leave them in the ground and lift as needed through winter; frost improves the flavour.

Trim off the leaves and fine roots. Celeriac keeps for weeks in the fridge or a cool place.

Growing in pots

Celeriac can grow in a deep, wide pot, at least 40 cm deep, but it is hard to keep a pot moist enough for long enough. Water every day in warm weather.

Using it

• Peel off the knobbly skin thickly, then mash, roast, add to soups and stews, or grate raw into salads such as remoulade.
• Cut celeriac browns quickly; drop pieces into water with a little lemon juice.