How to grow Radicchio

How to grow Radicchio - Description

Headed variety of radicchio

Radicchio is a spring or autumn leaf vegetable with a sharp, slightly bitter taste.
While some gardeners start the seeds indoors for later transplanting, most simply sow the seeds directly into the garden bed.
Radicchio is considered to be a gourmet type of vegetable.
Native to Italy, there are both open leaf and headed varieties, the headed varieties are the most popular.
Leaves are maroon or reddish in color, with white veins.

Radicchio is a member of the Daisy Family, and it is recommended that it should not be grown in the same soil as other family members for at least three years.

Radicchio likes fertile, well-drained soil in a mostly sunny location.
With a garden fork, work some compost or soil conditioner into the top 12 to 15 cm (5 to 6 inches) of soil.
Form rows in the garden bed approximately 60cm (24") apart.

Radicchio is always grown from seed.
Start seedlings growing indoors some four to six weeks before planting outdoors in the prepared growing bed.
- Sow seeds in a seed tray (flat) and cover the seeds lightly with 3mm (1/8") or less of compost.
- Seeds will sprout in 7-14 days.
Alternatively, sow radicchio seeds direct into your vegetable garden early in the season, once the frosts have passed or when the heat of the summer has ceased.

The final spacing of the transplanted seedlings should be 20 cm (eight inches) apart in rows 60 cm (two feet) apart.
If sowing seed direct, then sprinkle seeds lightly along the rows.
- It is fine if seeds overlap as the seedlings will be thinned later on.
- Cover the seeds with 0.5 cm (1/4 inch) of fine garden soil and gently water them in.
- Keep the bed moist until the seeds germinate.
- The radicchio seeds should germinate in about a week.
- When the seedlings are 0.5 cm (1 inch) tall, thin them so that the plants are spaced 20 to 40 cm (8" to 15") apart.
- To remove the unwanted seedlings, simply snip them at the soil line with a pair of scissors.

The photo to the right shows an open leaved radicchio, ready for harvesting.
Radicchio requires plenty of water and when the plants get drought-stressed, the leaves turn tough and bitter.
Add a generous layer of mulch around the base of the plants to cool the roots, prevent weeds and maintain adequate moisture.
If the plants send up a flower stalk instead of forming a head, cut off the stalk near the ground to encourage the formation of a new head.
Don’t be surprised when radicchio sprouts up green; this is typical and leaves will redden as they mature.
The plants grew to 12 in. high with large red and green leaves.
A light-excluding cover, e.g. an inverted pot, may be used during the latter phases of growth to produce leaves with a more pronounced colour contrast, simultaneously protecting against frost and cold winds.

Radicchio matures in about 80 to 90 days.
As soon as the heads are compact, firm and about the size of a cricket ball, simply cut the plant off at the soil line with a sharp knife.
Traditionally in the UK, the first cutting of all chicory heads was simply thrown away, and the tender, forced, second head was for the table.
However, improved varieties of radicchio, e.g. Rosso di Verona, and generally milder winters allow the West European cultivator to harvest two or more crops from a single planting.
If the head is cut off complete, just above the root, a small, new head will grow, especially if minimal frost protection is given. This process can be repeated a number of times.

For freshly picked heads simply brush any dirt off the exterior and put in a plastic bag and place in the refrigerator.
It will keep approximately a week.
When you are ready to use the leaves simply pull the leaves off the head and rinse in cool water.

Radicchio is popular in gourmet salads, adding colour and taste.
It is also eaten raw with a little olive oil.
It has a crisp, mildly bitter flavour, when it is allowed to mature in cool weather.
But, it takes on a strongly bitter taste, if it matures in the summer.
Radicchio is also grilled and baked.