Vegetable · Heading chicory
Radicchio
Cichorium intybus var. foliosumA bittersweet heading chicory grown specifically for the tight, wine-red heads that develop as nights turn cold — unlike loose-leaf chicories, it needs a real cool snap to color up and sweeten. Sown too early into warm, lengthening spring days it tends to bolt before heading at all. The one rule: time the main crop for fall, when the cold does the hard work of mellowing the bitterness.
Sow depth
½ in
Spacing
10 in · rows 12 in
Sun
Full sun
Germination
7–14 days
Time to harvest
65–90 days
Difficulty
Moderate
When to sow radicchio
- Sow from about 3 weeks before your last expected frost until about 1 week before your last expected frost.
- Sow from about 14 weeks before the first expected autumn frost until about 11 weeks before the first expected autumn frost.
Direct sow shallowly into a fine, moist seedbed.Time the main crop for late summer so heads form as fall nights cool.Thin gradually as seedlings crowd, giving each head room to fill out.
Keep soil evenly moist — drought stress only deepens the bitterness.Weed while plants are young; established heads shade out most competition.No blanching needed — outer leaves wrap the heart and self-blanch it.
Cut heads once dense and tight, feeling firm when squeezed.A light frost only improves flavor, turning the color deeper and sweeter.Use heads promptly after cutting — they don’t store as long as ordinary cabbage.
Companion plants
Onions and dill planted nearby are thought to help mask radicchio’s leaves from aphids and cabbage-family pests.
Watch out for
Slugs — Shelter in the dense, damp heads as they form. Clear mulch away from the base and check plants at dusk.Aphids — Cluster in the cool, humid weather radicchio loves. Rinse off with water or encourage ladybirds early.