When to plant Radicchio in Temperate Australia

Temperate zone — applies to Sydney, Melbourne, Adelaide, Perth, Newcastle and similar areas. Growing elsewhere? Cool · Subtropical · Tropical · Arid.

Sow radicchio direct from September to December, covering the seed 5 mm deep. Germination is quick at 7–14 days, and heads mature in 80–90 days, which places harvest through late spring and into autumn as temperatures cool. Space or thin plants 20–30 cm apart with 30–40 cm between rows in full sun to part shade. In temperate gardens around Melbourne and Adelaide, radicchio colours up and tightens its head best as the weather cools, so timing the crop to mature out of peak summer heat gives the sweetest, firmest result.

Sowing calendar — temperate zone

Green months are your sowing window: September to December.

Growing notes

Radicchio is a hardy chicory grown for its bitter, red-veined heads, and it belongs to the cool end of the temperate season. While the sowing window runs from September to December, the crop performs best when it heads up as the weather cools rather than in the heat of midsummer. Full sun, steady moisture and a fertile, free-draining bed produce the tightest hearts.

The defining feature of radicchio is bitterness, and the way to temper it is cool weather at heading. Plants that mature in hot conditions turn intensely bitter and are prone to bolting straight to flower without forming a head, which is the most common disappointment. To avoid it, time sowings so heads fill during cooler spells and keep water consistent, as stress and heat both trigger bolting.

Many varieties also benefit from being cut back: shearing a loose plant to about 5 cm above the crown in cool weather prompts it to regrow a tighter, sweeter red heart. Keep an eye out for slugs and snails sheltering in the leaves, especially after rain around Newcastle and Sydney, and pick them off at dusk. Harvest the whole head once it feels firm, and use the crisp cool-season leaves in salads where their bitterness is a feature rather than a fault.

Radicchio at a glance

Common questions

when do you plant radicchio in temperate Australia

Sow direct from September to December, but aim for heads to mature as the weather cools rather than in peak summer heat. Cool conditions at heading give firmer, sweeter, less bitter radicchio. It matures in 80–90 days.

why is my radicchio so bitter

Radicchio grown through hot weather turns intensely bitter and may bolt without forming a head. Timing the crop to mature in cool conditions and keeping water steady tempers the bitterness. Cool weather is the key to a sweeter head.

why won't my radicchio form a head

Heat and stress cause radicchio to bolt to flower instead of hearting up. Keep watering consistent and time sowings so the plant matures in cooler weather. Some varieties also heart better after being cut back to about 5 cm.

can you cut radicchio and let it regrow

Yes, shearing a loose plant to about 5 cm above the crown in cool weather often prompts it to regrow a tighter, sweeter red heart. This is a common trick for improving quality in temperate gardens.

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