How to grow Radicchio in New Zealand
Radicchio is an Italian chicory with striking red and white leaves and a pleasantly bitter bite for salads, grilling and roasting with balsamic. Its heads tighten and colour up in cool weather, and the bitterness mellows after a chill, so it suits cooler and southern districts well. In the warm north, sow from late summer into autumn for the best heads.
📖 Our full guide: How to Grow Radicchio in New Zealand
At a glance
When to sow by region
| Region | When to sow | Regional note |
|---|---|---|
| Northland | August to October, January to April | |
| Auckland | August to October, January to April | |
| Waikato & Bay of Plenty | August to October, January to April | |
| Central North Island | August to October, January to April | |
| Wellington & Lower North Island | August to October, January to April | |
| Nelson & Marlborough | August to October, January to April | |
| Canterbury | August to March | Keep sowing through Nov to Dec with steady watering. Make the last sowing in Mar so the crop is ready before winter growth stops. |
| Otago & Southland | September to February | Start spring sowings in Sep; the soil is too cold before then. Cool summers let you keep sowing through Nov to Dec. Make the last sowing in Feb so the crop is ready before winter growth stops. |
| Central Otago | September to February | Start spring sowings in Sep; the soil is too cold before then. Keep sowing through Nov to Dec with steady watering. Make the last sowing in Feb so the crop is ready before winter growth stops. |
Not to be confused with: Chicory and endive, close relatives, and red cabbage, which looks similar but is a brassica.
Where to plant
Grow radicchio in full sun in well-drained soil that stays moist. Cool weather gives the best colour and tightest heads; summer heat makes it bolt and more bitter.
- Northland, Auckland and the Bay of Plenty: sow from late summer into autumn for heads over winter, and again in late winter to early spring.
- Canterbury: keep sowing through November and December with steady watering, and make the last sowing in March.
- Otago, Southland and Central Otago: start spring sowings in September, keep sowing through early summer, and make the last sowing in February.
Choosing a variety
- Round-headed Chioggia types form tight, cabbage-like red heads.
- Treviso types have long, upright red leaves with white ribs.
- Variegated types such as Castelfranco have cream leaves splashed with red and are milder.
How to plant
- Sow seed in trays or direct, cover lightly and keep moist.
- Transplant seedlings at least 30 cm apart into a prepared bed.
- Mulch with pea straw and water in well.
- Make successive sowings every few weeks to spread the harvest.
Watering and feeding
Water regularly so the soil stays evenly moist; dry soil makes the leaves tough and very bitter and causes tipburn on the leaf edges. Feed lightly with a liquid fertiliser while plants are growing.
Pruning and care through the year
- Keep the bed weeded and watch for slugs and snails on young plants.
- In wet weather, remove any rotting outer leaves at the base to stop rot spreading into the head.
- Plants that have not formed a head by winter often heart up as the weather cools.
Harvesting
Pick individual leaves as they grow, or cut whole heads at the base when they are firm. Cutting a head above the base can let the plant regrow small heads. Soaking leaves in cold water for a while softens the bitterness.
Growing in pots
Radicchio grows well in a pot or trough of quality potting mix in sun. Keep the mix evenly moist.
Companion planting
Radicchio is an easy cool-season neighbour.
Good companions
Pests and diseases
Slugs, snails and aphids are the main pests; rot at the base is the main disease in wet weather.
Pests to watch for
- Aphids Small insects deep in the heart and under the leaves.
- Slugs Holes in the outer leaves and slime trails.
- Snails Seedlings eaten overnight.
Diseases to watch for
- Bottom rot Lower leaves rot where they touch wet soil and the rot spreads into the head. Mulch and remove affected leaves.
- Tipburn Brown, papery leaf edges, linked to uneven watering and hot spells.
Common questions
Why is my radicchio so bitter?
Radicchio is naturally bitter, but heat and dry soil make it much stronger. Grow it in the cool months, keep it watered, and pick after a cold spell, when the flavour mellows. Soaking the leaves in cold water also helps.
Why isn't my radicchio forming a head?
Heads form and colour up as the weather cools. Plants sown in warm weather often stay leafy until autumn. Sow at the right time for your region and give plants 30 cm of space.
When should I sow radicchio?
In the north, from late summer into autumn, and again in late winter. In the south, from spring into early summer, with the last sowing in February or March. Choose your region at the top of the page.
How do I cook radicchio?
Use it raw in salads, or cut it into wedges and grill or roast it with olive oil and balsamic vinegar, which softens the bitterness.
Is radicchio the same as chicory?
Radicchio is a type of chicory, grown for its coloured heads. Other chicories include witloof and the leafy types.
Sources we checked: Yates NZ: How to grow radicchio; Kings Seeds: Guide to growing endive, chicory and lettuce.