Endive, or Chicory—This, for salad, takes the same place in winter that lettuce occupies in summer and when well grown is equally valuable. There are two very distinct varieties; [...] The other sort is the "Escarole" of the French, and is sweet in flavor, with a wider and flatter leaf, which comes earlier in the season but does not usually form so close a head, although it is preferable in flavor. [...] Sow twice, early in July and the first week in August. The broad leaf, (which is the Escarole,) for the first crop, and some White Curled for the second crop.
Source: wiktionary