The definition of radicchio varies depending on where you are, but head chicories can be used for baby or young leaf production, or grown out for the delicious mature heads. Plant after frost, when the soil is beginning to warm (about 55-75 F), 1/8 inch deep and loosely covered. Many folks will grow chicories as a fall crop, planting in mid to late summer. You may need to plant in succession to discover the best planting time for your region. The red-leaf varieties need cool weather, perhaps even frost, to obtain their coloring and best flavor. Chicories have a wide range of uses, from fresh cut salad greens, to heavier greens for braising.