Sow seeds of Witloof chicory in May or June. The soil must be fertile. Any manure or garden compost added prior to sowing must be very well rotted. Sow thinly in drills 1cm (1/2 in) deep, spaced 30cm (1 ft) apart. Keep down annual weeds by hoeing. When the plants are about 5cm (2in) high, thin to 23cm (9in) apart in the rows. Except for weeding now and then, no further cultivation is necessary.
By November the plants will have made roots resembling parsnips. These are dug a few at a time. Cut back the top growth to 2.5cm (1 in) above the crown and reduce the length of the roots by the same amount. Discard any thin or fanged roots.
Pack the prepared roots closely together in boxes or large clay flower pots filled with damp potting soil.
Unless blanched in absolute darkness, the chicons, as the blanched shoots are called, will be yellow and bitter. Exclude light by making a specially darkened pit beneath the greenhouse staging.
Several sheets of black polythene should be draped above and around the boxes or the pit. Inverted flower pots, with drainage holes covered, may be stood over pots of roots. Reasonably quick growth occurs at 60°F (16°C), but in the garden shed or the cold greenhouse, the chicons will take two months or so to develop.
When the blanched chicons are 16cm (6in) tall, cut them off at soil level.
Good cookery books give recipes, but the blanched chicons are more generally used in salads. The forced roots should be added to the compost heap.