Crops Chicory (Cichorium intybus)

Young plants

Chicory is a hardy biennial or short-lived perennial. There is a strong, deeply-penetrating taproot, which may become swollen with carbohydrate reserves in varieties developed for inulin production.

Developing plants

During the first season, a clump of shiny oblong leaves is produced; these have a prominent midrib, and may be either rounded or pointed at the ends. The tough, ridged flowering stem appears during the second summer, and may grow to a height of 150 cm in cultivated types.

Flowe

There may be leaves and branches on lower portions of the stem, the upper parts bearing the characteristic azure-blue flowers, which are carried on very short individual stalks. The flowers open successively upwards, though they often close during dull weather. The crop requires deep well-drained soils; while it will tolerate drought, productivity will be affected.

Seeds

Sowing takes place during April when the soil is sufficiently warm. For inulin production, established population should be 15-20 plants per square metre in rows some 45-50 cm apart; early growth is slow, so weed control is important, and some herbicides are available. Chicory responds well to applications of the main plant nutrients, up to 150 kg nitrogen, 200 kg phosphate and 250 kg potash per ha being recommended for good yields. Plants are susceptible to soil-borne diseases caused by Sclerotinia and Rhizoctonia spp., so proper crop rotation is important.

Mature roots

Roots are normally lifted during October and November, often using the same technique as for sugar beet: yields are also comparable with beet, up to 50 t per ha of fresh roots being produced, giving about 9 t inulin per ha. In many agricultural systems in Europe, chicory seems likely to be a more reliable producer of inulin than Jerusalem artichoke, since crop yield is considerably less variable. Breeding and development work are continuing in Belgium, the Netherlands, France and Germany to improve yield levels, root shape, and disease resistance of inulin-producing cultivars and to optimise cropping systems. Meanwhile, chemical processes are being investigated which may result in derivatives of inulin being shown to be useful for a wide variety of industrial applications, for example in the production of detergents, solvents, polymers, pharmaceuticals and plant protection agents.