When to plant radicchio?

When, by region

April and May indoors, June and July outdoors, late May or early June, 1 cm (½ in), 30 cm (1 ft), 5 cm (2 in), a pot of 30 cm (1 ft), late summer to mid-autumn and the frost are from the RHS, for non-forcing chicory, the group in which it puts radicchio. Summer, and harvest in autumn and winter, are from Campania, which names no month. Sicily has no sowing chapter. At least one cycle, and at least 1 year, are from Umbria 2025, which writes no month. Lettuce, with its months, is in when to plant lettuce. The months are in the April calendar, May, June, July and August.

April indoors, June outside

The RHS separates three chicories. The forcing one, Belgian, is sown outdoors in May and June, and it is not radicchio. Radicchio, or red chicory, sits with the non-forcing chicories, along with the sugarloaf type. For those, indoor sowing is April and May, and outdoor sowing June and July. Seed goes 1 cm (½ in) deep, in rows 30 cm (1 ft) apart. Thin to 30 cm (1 ft). Radicchio types want at least 30 cm (1 ft), so the round head has room. Baby leaves are thinned to 5 cm (2 in), and they can be repeated: outdoors in spring and summer, in a greenhouse in late winter and in late summer or early autumn.

Young plants go out from late May or early June, once the weather is warm enough. Cold sends them to flower. The planting calendar marks May and June. The pot is in starting seeds indoors.

Campania, in summer

In Campania the chapter covers chicory and radicchio. Chicories, because the cycle is short, can be grown through the year, as a catch crop or as a main crop. The sentence on coloured-leaf radicchio is narrower: it is generally transplanted in summer, with autumn and winter harvests. A month name is not written. Outside mountain zones the rotation is five years, with at least three crops and at most one repeat. Two cycles in the same year count as one year.

In Sicily there is no sowing chapter. The name appears in a nutrient table, not as a date. Umbria, in 2025, has the sheet and does not write the month. With a single cycle a year, return after at least one cycle of crops that are not composites. With several cycles in a row in the same year, after at least 1 year, or one main crop, of crops outside that family. Lettuce is in when to plant lettuce.

Heads from late summer

Radicchio and sugarloaf heads, for the RHS, are ready from late summer to mid-autumn. Cut them before frost, or cover them. The red colour arrives from late summer, as the days shorten and temperatures fall. The stump, left in place, may reshoot a second, smaller head. In a pot, a container at least 30 cm (1 ft) wide. Cover is in mulching, and the pot in the container garden.

In crop rotation salads go wherever suits you, without repeating them too often. In Umbria radicchio, on a single cycle, waits for at least one cycle of crops that are not composites.