🟣 Radicchio

Radicchio is a red-leaved Italian chicory with a bold, pleasantly bitter flavour and a striking colour. It is hardier than lettuce, so provides fresh salads in autumn and winter, and it is less demanding to grow than many people assume.

There are round-headed types such as Palla Rossa, and elongated ones such as Treviso. The red colour develops as the weather cools, and the bitterness mellows after cold or when the plants are blanched. They are a good crop for medium or large plots.

Varieties to try

Palla Rossa (round, red heads)Rossa di Treviso (elongated, tapered heads)Rossa di Verona (reliable red heads)Castelfranco (variegated, creamy-green and red leaves)

Sow in June and July for a crop in autumn and early winter. Sowing too early causes the plants to bolt rather than head up. Sow thinly in a seedbed or in modules, 1 cm deep, and thin or transplant to 25–30 cm apart when the seedlings are 10 cm tall.

Choose a sunny site with fertile, well-drained soil. In very dry conditions, water the drill before sowing. Pests rarely trouble the young plants but slugs may nibble, so protect with traps. Plants establish well, and the roots develop deeply, making them reasonably drought-tolerant.

Top tips

• Sow in June–July; earlier sowings bolt.
• Thin to 25–30 cm.
• Keep the soil moist during germination.
• Choose a sunny site.

Water regularly through the summer, keeping the soil moist but not waterlogged. Hoe between plants to control weeds. Cut off the foliage 2.5 cm above the ground in late summer or autumn to encourage a tight head of leaves to form; this also makes the plant produce a neat, red, round head of leaves.

Slugs and snails are the main problem, along with aphids. Fleece or a cloche in late autumn protects the heads from frost damage and wet. Radicchio is hardy but heads can suffer in very hard winters; harvest before prolonged freezing.

Top tips

• Cut the foliage back in late summer to promote tight heads.
• Water in dry periods.
• Protect heads with fleece in frost.
• Use slug traps.

Watch out for

Slugs and snailsAphidsBolting from early sowingFrost damage to heads

Cut heads when they feel firm and are about the size of a grapefruit, from October to December. Cut just above ground level with a sharp knife, leaving the root in the soil; many plants will re-grow loose heads in spring. Harvest before hard frosts to protect the heads.

To tame the bitterness, you can lift whole plants in November, trim the leaves to 3 cm and pack the roots in boxes of damp compost in a dark, cool place. The pale, tender new leaves (chicons) grow in three to four weeks and are sweet and delicate.

Top tips

• Cut firm, grapefruit-sized heads.
• Harvest before prolonged hard frost.
• Force roots in the dark for pale, sweet chicons.
• Leave the root; it may regrow.

Slice radicchio into salads for colour and crunch, balancing the bitterness with sweet fruit, nuts, honey or a creamy dressing. It is also delicious grilled or roasted, which softens the flavour and turns it sweet and smoky. Add it to risotto, pasta and pizza, or braise it gently in butter and wine.

Whole heads keep in the fridge for two weeks, wrapped in damp kitchen paper in a bag. Remove the outer leaves before eating. Cooked radicchio can be frozen, but fresh leaves lose their crisp texture on freezing.

Top tips

• Soak shredded leaves in cold water to soften the bitterness.
• Grill wedges with olive oil and balsamic vinegar.
• Balance with honey, pears or walnuts.
• Add to risotto at the end.