Radicchio is an Italian salad plant related to chicory. The distinctive plant grows in a rich maroon color with white veins and has a peppery flavor that adds a textural bite to salads. Radicchio is sometimes grilled or roasted, making a pleasant counterpoint to other grilled vegetables. It is growing in popularity and can be found in most produce sections. Radicchio has been in cultivation in the Mediterranean for hundreds of years and is used in a variety of Mediterranean dishes.
Radicchio resembles lettuce most in appearance, although it is not in the lettuce family. It forms tight heads of leaves furled around a central core and grows low to the ground. Radicchio makes a startling splash of color in the garden, and its natural bitterness makes it less subject to depredation by garden pests.
When picking out radicchio in the grocery store, look for larger heads with looser outer leaves. Tight small heads have probably been excessively handled and may have drier cores. Radicchio can keep under refrigeration for one week, and the leaves should be rinsed before use.
To grow radicchio, plant seeds or seedlings in early spring and late fall, because the plant prefers cooler temperatures. It has a shallow root system, and therefore prefers frequent light watering to saturation. Plant radicchio eight to ten inches (20 to 25 centimeters) apart to allow the plants room to form heads. Radicchio will mature in approximately 80 days. Harvest with a sharp knife and remove the roots from the soil before preparing it for the next crop.
For grilling or baking, radicchio leaves can be wrapped whole around other produce items or meats, or prepared separately. If grilling separately, quarter the heads lengthwise, sprinkle them in olive oil and salt for flavor, and grill until the core is tender and the outer leaves brown, which may take approximately 30 minutes with occasional rotations. Sprinkle with asiago or another cheese directly before serving. Grilled radicchio can be made sweeter by mixing it with sweet onion or another caramelizing vegetable.
In salads, be aware that radicchio's bitter flavor is distasteful to some consumers, so it should not be used to excess unless guests are familiar with chicory and other bitter greens. It makes a bright addition to a green salad, standing out with its excellent maroon color and peppery flavor. It does, however, brown easily, and should not be chopped too early.