Tuesday, March 2, 2010

Growing Radicchio in Kihei

Radicchio is an Italian green from the chicory family. It requires our coolest winter weather to grow well. I plant radicchio seeds from mid-October through mid-November. Most varieties need 3 months from seed to maturity.

Radicchio is slow to bolt but like many of the red or butter lettuces, it's not cool enough in Kihei to initiate heading or to turn the leaves red in all varieties.
Palla Rossa
When mature, Palla Rossa looked similar to a butter-head lettuce.

Since radicchio doesn't produce a compact head in the Keonkai climate, and can't be used as a grilled veggie, I use the center leaves in salads. Like endive and escarole it's less bitter when it's blanched or grown during a cooler winter. I've grown many varieties of radicchio and my best results were with the varieties featured in this post.

Pan di Zucchero
Gourmet Seed
Seeds From Italy
In the photo the outer leaves were pulled open to expose the beautiful romaine like heart.

 Indigo is an F1 hybrid that was noted to be heat tolerant.
Radicchio is easy to grow in containers. All of the varieties in this post were grown in containers with a soil depth of at least 5 inches. In a temperate climate radicchio, endive and escarole are perennials. The heads can be cut off within an inch of the crown and the leaves will grow back. 

I plant radicchio in an organic potting soil amended with OMRI azomite, green sand and an organic all purpose fertilizer.The plants needed daily water and twice-monthly applications of fish emulsion or an organic all-purpose fertilizer once a month. Radicchio, like endive and escarole, is sensitive to the Kihei winter sun - it grew best with sun in the morning and diffused light or shade in the early afternoon.

One of the best things about growing radicchio is that it's not bothered by any of  the destructive Kihei insects or cabbageworms. It's one of a few salad greens that doesn't need to be covered with a row cover or tulle.

Gourmet Seed and Seeds From Italy have large selections of radicchio seeds. Indigo is available from The Natural Gardening Company

Rossa di Treviso Rio S Martino and an Indigo

Radicchio grows better in Maui Meadows than in Keonekai. Palla Rossa still didn't head but Indigo formed small red round heads. Rossa di Treviso formed more compact heads with red variegated leaves at the center.


  1. Wow that is a lot of radicchio. I couldn't imagine eating it all.

  2. Hi Daphne! Radicchio and endive have been great here as they've never bolted. This year I tried a lot more varieties. So far I've only found one lettuce I can grow to maturity that doesn't bolt early due to the heat. It's been great having so many different salad greens this winter - I wish I could grow them all year!

  3. i ave not grown Radiccio before, One of my daghters is an excellent gardner, we used my own compost ( several years accumalation ), my daughter remarked that it was GOLD DUST!, also she bought some compost from the supplier, and so several plants were placed in the veggie beds with the combination of the two composts. I have never seen plants grow so fast, they are like Triffords, the Spinach just speeded ahead and was very disapointing as it bolted like a weed. The radiccio almost did as badly as regards bolting. Should we have added some ordinary earth into the mix,also at the time of planting, mid-May, the weather was very warm here in Cornwall. I would like your comments and advice please

  4. Hi Frances! Lots of gardeners plant directly in compost. As long as it's well rotted it shouldn't burn the plants or cause any problems. Spinach is a fall/winter vegetable. It will grow under row covers in the snow. Matador Spinach, a Franchi seed is the only spinach I'm aware of that grows in warm weather.

    Radicchio is a cooler weather vegetable too and it's normally planted in the fall. You might plant your spinich and radicchio later next month or in September. If you want to grow radicchio for summer harvesting try planting the treviso varieties - they're slower to bolt. The heading types need cooler weather.

  5. I ordered some seeds today based on your blog! Mahalo from the Big Island!