How to Grow Chicory in Australia

Chicory (Cichorium intybus) is a leafy vegetable in the daisy family, Asteraceae, grown for bitter leaves, firm heads and the roots forced for witloof. Its leaves colour and sweeten as the nights turn cold, which makes it a natural autumn and winter crop across much of Australia. The usual mistake is sowing heading types in spring.

Three mistakes that matter

1. Sowing heading types in spring. Heat and long summer days push radicchio and sugarloaf to bolt (run to flower and seed), so spring sowings often flower before they head. Sow heading types from late summer into autumn, in the months given in When to plant.
2. Crowding the plants. Radicchio and sugarloaf need room to wrap their leaves into a heart, and crowded plants seldom form good heads. Thin or transplant heading types 25 to 30 cm apart, as set out in Thinning.
3. Letting plants go dry or old. Water stress, heat and late picking all make chicory harshly bitter and tough. Keep the soil evenly moist from sowing to harvest, and cut each head as soon as it feels firm.

When to plant

Chicory seed germinates in soil from about 10°C to 25°C. Heading types take about 11 to 16 weeks and witloof roots 4 to 5 months, so time each sowing to mature in the coolest months. Leaf types are more forgiving and can be sown through much of the year in mild coastal districts.

Canberra growers have a narrow window for heading types, from the summer solstice to the first week of January. At the hot edge of any window, raise seedlings in trays in light shade and plant them out as the heat breaks.

Site, soil and setup

Container growing

Leaf chicories and single radicchio heads grow well in pots, but witloof roots are better in the ground. Use a pot at least 30 cm across and 20 cm deep, with good drainage holes. Fill it with 10 to 15 L of premium potting mix with some compost added. One pot suits one radicchio or sugarloaf, or two or three leaf chicories cut young. Good choices are 'Red Ball', 'Red Rib', 'Italiko Rosso' and 'Catalogna Long Green'.

• Water: pots dry out faster than beds, so check them daily in warm weather and water before the mix dries out.
• Feed: from the first true leaves, fish and seaweed blend at 25 mL per 9 L, fortnightly. Or use an all-purpose soluble powder (NPK around 23-4-18 to 27-5-9) at label rate, fortnightly.
• Position: full sun in autumn and winter; move the pot into afternoon shade during hot spells.

Sowing Seeds

Raise heading types in cell trays for transplanting, and sow witloof and leaf types straight into the bed.

Choosing a type

'Italiko Rosso' is sold as red dandelion, but it is a leaf chicory, not a true dandelion (Taraxacum). Endive (Cichorium endivia) is a separate crop, and so are lettuce and rocket.

Starting in trays

• Sow two seeds per cell of seed-raising mix, 5 mm deep.
• Keep the mix damp and out of hot sun; seedlings usually emerge in 4 to 14 days.
• Snip the weaker seedling in each cell at mix level.
• Plant out at three or four true leaves, about 3 to 4 weeks from sowing, and before seedlings are 30 days old.
• Harden them off first (a week of gradually longer spells outdoors); see hardening off seedlings.

Sowing direct

• Rake the bed to a fine surface and water it the day before sowing.
• Sow thinly, 5 mm deep, along rows 30 cm apart.
• Sow witloof where it is to grow, since its long taproot resents moving.
• Keep the surface damp until the seedlings are up.
• Thin in stages to the spacings in Thinning.

Care by growth stage

Feeding decides flavour as much as water does: moderate feeds suit chicory, and too much nitrogen gives lush but bland leaves. Weeks count from sowing.

Water in the morning, at the base of the plants, so the leaves dry quickly. Chicory has a deep taproot, so a deep soak does more than a daily sprinkle.

Thinning

How far apart to thin depends on the type: heads need the most room, leaves picked young the least.

• Snip unwanted seedlings at soil level so the taproots you keep stay undisturbed.
• Eat the thinnings in salads.
• Pinch out flower stems on leaf types as soon as they appear.
• Pull off yellowing or rotting outer leaves at the base of heading types, so air can move around the heart.

Companion planting

Good neighbours share chicory's deep, loose bed without sharing its aphids or its sclerotinia rot.

Grows well with

• Carrot, which likes the same deep, stone-free soil and belongs to a different plant family.
• Onion, which resists sclerotinia rot and so does not build it up in the soil.
• Tomato, whose tall summer growth gives late-summer chicory seedlings some afternoon shade.

Keep apart

• Lettuce and endive, which host the same currant-lettuce aphid.
• Beans and peas, which also host sclerotinia rot, so the fungus builds up in shared soil.

Harvesting Leaves

Pick leaf types as soon as the leaves are big enough to eat, and cut heading types once the head feels firm when squeezed.

• Take the outer leaves of leaf chicories first, and leave the centre to keep growing.
• Cut radicchio heads at the base with a sharp knife once they are firm and 10 to 15 cm across.
• Peel away the green outer leaves of 'Red Ball' to find the red ball inside.
• Cut sugarloaf when the head is tall and firm with a pale centre.
• Leave the stump in the ground, since the root often reshoots a second crop of small leaves.
• Pick in the cool of the morning, when leaves are crisp.

Wrap heads loosely and keep them in the fridge, where radicchio can keep for up to three weeks. Keep loose leaves in a perforated plastic bag in the fridge and use them within a few days. Use radicchio raw in salads, or grill, roast or braise it to mellow the bite; cook leaf chicories as you would spinach.

Forcing witloof

The leafy plant builds the root, and forcing regrows that root in the dark as a chicon. Only one Australian farm grows it commercially, near Clyde in Victoria, so a home crop is a rare treat.

1. Lift the roots in late autumn or early winter, once they are 3 to 6 cm across at the top.
2. Cut the leaves off 2 to 5 cm above the crown, without damaging the central bud.
3. Trim the roots to 15 to 25 cm long, and hold them in a cold, dark place close to 0°C for 2 to 3 weeks.
4. Stand them upright, 3 to 5 cm apart, in a deep pot of damp sand or loose soil. Cover the pot so no light gets in.
5. Keep the pot at 10°C to 15°C and the sand just damp.
6. Cut each chicon just above the root when it is firm and 10 to 15 cm long, usually after 3 to 4 weeks.

Store chicons wrapped in paper in the fridge, out of the light.

Common problems

No heart, or no red. The types in Choosing a type that form no round head are picked as leaves. Heading types that stay open or green usually lacked room or cold nights; see When to plant.

Patchy germination. Chicory often comes up unevenly in open ground. Raise heading types in cell trays and keep the surface damp. Read more

Loose or green chicons. Light turns chicons green and bitter, and undersized roots give loose, open chicons. Force only well-grown roots, in complete darkness.

Seedlings everywhere. A plant left to set seed in summer can drop large numbers of seed, and chicory already grows as a roadside weed. Cut the flower stems before the seed ripens.

Pests and diseases

Chicory is fairly trouble-free, and snails and aphids cause most of the damage. Use only sprays whose label names the pest and chicory, or a crop group that includes it, and keep to any withholding period.

Common garden snail (Cornu aspersum) and slugs. They chew irregular holes and leave slime trails, and they can wipe out a sowing of seedlings in wet weather. Pick them off in the evening, or scatter an iron-based snail bait thinly, never in heaps. Keep dogs and children away from it, since even iron baits can poison a dog. Read more

Currant-lettuce aphid (Nasonovia ribisnigri) and other aphids. Small aphids, yellow-green to pink, hide under leaves and deep in the heart, curling and stunting growth. Wash them off with a strong jet of water, or spray insecticidal soap into the heart. Read more

Sclerotinia rot (Sclerotinia sclerotiorum and S. minor). In cool, wet weather the base turns soft and water-soaked under white, fluffy fungus, and the plant collapses. Pull affected plants and bin them, because the fungus survives in soil for years.

Damping off (Pythium species and Rhizoctonia solani). Seed rots before it emerges, or seedlings collapse at soil level, most often in wet mix. Use fresh seed-raising mix and water only enough to keep it damp. Read more

Prevention first

• Clear boards, pots and leaf litter from bed edges, where snails hide by day.
• Check leaf undersides and the hearts weekly for aphids.
• Space plants as in Thinning, so air moves freely between them.
• Pull volunteer lettuce and prickly lettuce nearby, which shelter currant-lettuce aphid.

Tips

1. For a paler, sweeter heart, tie the outer leaves of a radicchio or sugarloaf up over the centre about a week before cutting. An upturned terracotta pot does the same job.
2. Sow two or three types with different days to maturity in the same window. The harvest then spreads over several weeks instead of arriving at once.
3. Let one 'Red Rib' plant flower for the bees; see Common problems for when to cut the stems.
4. Sow a few extra witloof and pick them as a bitter salad green, leaving the rest untouched to grow roots for forcing.