How to Grow Globe Artichoke
This herbaceous perennial, which is more or less winter hardy in Britain, is grown for the young flower heads which are made up of a number of scales with fleshy bases. It is extremely popular in France and large areas are grown in Britanny but, although the plant has been in this country since the fifteenth century, we grow very few. The fleshy receptacle or ‘heart’ of the flower head is also eaten in the same way as the scales while young leaf stalks can be blanched in the same way as cardoons (q.v.) for use in the autumn.
The globe artichoke is a member of the daisy family. Since it grows to a height of 1.5 metres (5ft) each year it requires a considerable amount of space. It is, however, another dual-purpose plant with ornamental foliage and an attractive flower.
Soil and fertilizer requirements
Like all perennial plants globe artichoke must be grown on well prepared, manured and weed-free land. Complete winter hardiness can only be expected in sheltered districts—hence the importance of the coastal regions of Brittany—and on light, well-drained soils. Some plants will rot during the winter when grown on wet, heavy soils. This is not a long-lived perennial—the productivity falls off after 4 or 5 years—so regularimprovement is possible. The plants should be top-dressed each spring with 50 to 100g per m2 (2 to 4 oz per sq yd) of general purpose fertilizer.
Plant raising and planting
Globe artichokes can be raised from seed but, as with, the resultant plants will be unpredictably variable. Vegetative propagation from offsets is the best method of raising new plants. Cut off the 15 to 20-cm (6 to 8-in) long shoots with a sharp knife from selected, true-to-type parent plants either in March or in October. Spring-taken offsets are immediately planted into their final positions at 75-cm (30-in) square spacings but autumn-taken offsets are potted into 9-cm (3-1/4-in) pots and kept in a cold frame until the following spring when they are also planted as indicated. Firm planting and care during establishment are essential. One fifth or a quarter of the globe artichoke bed should be taken up and replaced with young plants each year so a regular propagation programme must be followed.
Remove any over-wintered protectant material just as growth begins in the spring and fork in the top-dressing fertilizer. Rapid growth is necessary if tender, succulent ‘chokes’ are to be produced. Water may be needed in dry years while straw or grass cutting mulches will restrict weed growth. Tidy up the plants by cutting out dead, unwanted material when growth has died down in the autumn. In all but the most sheltered coastal and south-western districts, the plants must be protected with a straw covering during the winter.
Heads will be ready for cutting from mid-summer onwards. Cut the terminal (’king’) heads first. Newly planted offsets will often produce a few heads in the first year but productivity should build up in the next three years. The terminal buds will have the largest heads but the later maturing lateral buds are also very tender. Harvesting at an early stage is imperative in order to get the best possible flavour and ensure continued cropping.
Pests and diseases
Few attack this crop.
Named cultivars are not commonly available in Britain but offsets should always be purchased from a reliable nurseryman. ‘Gros Camus de Bretagne’ and ‘Gros Camus d’Angers’ are two widely grown and popular French cultivars.