Cardoon

Cardoon
Plants in bloom, Costa Vicentina National Park, Portugal
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	Asterids
Order:	Asterales
Family:	Asteraceae
Genus:	Cynara
Species:	C. cardunculus
Binomial name
Cynara cardunculus L.
Synonyms
Cynara scolymus L.[1]

The cardoon (Cynara cardunculus), also called the artichoke thistle, cardone, cardoni, carduni or cardi, is a thistle-like plant in the aster family Asteraceae. It is the naturally occurring form of the same species as the globe artichoke, and has many cultivated varieties. It is native to the western and central Mediterranean region, where it was domesticated in ancient times.

Description

The wild cardoon is a stout herbaceous perennial plant growing to 0.8–1.5 m tall, with deeply lobed and heavily spined green to grey-green tomentose leaves up to 50 cm long, with yellow spines up to 3.5 cm long. The flowers are violet-purple, produced in a large, globose, massively spined capitulum up to 6 cm diameter.^[1][2][3][4]

It is adapted to dry climates, occurring wild from Morocco and Portugal east to Libya and Greece and north to France and Croatia; it may also be native on Cyprus, the Canary Islands and Madeira.^[5] In France, it only occurs wild in the Mediterranean south (Gard, Hérault, Aude, Pyrénées-Orientales, Corsica).^[3] It has become an invasive weed in the pampas of Argentina,^[4] and is also considered a weed in Australia and California.

Cultivation

Cultivated cardoon foliage, Madrid Royal Botanical Garden. Compare the non-spiny leaves with the wild plant, above right.

There are two main cultivar groups, the cardoon (Cynara cardunculus Cardoon Group, syn. C. cardunculus var. altilis DC), selected for edible leaf stems, and the artichoke (Cynara cardunculus Scolymus Group, previously distinguished as Cynara scolymus or C. cardunculus var. scolymus (L.) Fiori), selected for edible flower buds. They differ from the wild plant in being larger (up to 2 m tall), much less spiny, and with thicker leaf stems and larger flowers, all characteristics selected by man for greater crop yield and easier harvest and processing.^[1][6] Wild and cultivated cardoons and artichokes are very similar genetically, and are fully interfertile, but only have very limited ability to form hybrids with other species in the genus Cynara.^[1]

The earliest description of the cardoon may come from the fourth century BC Greek writer Theophrastus, though the exact identity of this plant is uncertain.^[1] The cardoon was popular in Greek, Roman, and Persian cuisine, and remained popular in medieval and early modern Europe. It also became common in the vegetable gardens of colonial America. They fell from fashion only in the late 19th century. In Europe, cardoon is still cultivated in France (Provence, Savoie, Lyonnais), Spain and Italy. In the Geneva region, where Huguenot refugees introduced it in about 1685, the local cultivar 'Argenté de Genève' ('Cardy')^[7] is considered a culinary specialty. "Before cardoons are sent to table, the stalks or ribs are blanched tying them together and wrapping them round with straw, which is also tied up with cord, and left so for about three weeks".^[8] Cardoons also are common vegetables in northern Africa, often used in Algerian or Tunisian couscous.

Cardoon, raw

Nutritional value per 100 g (3.5 oz)
Energy	71 kJ (17 kcal)
Carbohydrates	4.07 g
- Dietary fibre	1.6 g
Fat	0.1 g
Protein	0.7 g
Thiamine (vit. B1)	0.02 mg (2%)
Riboflavin (vit. B2)	0.03 mg (3%)
Niacin (vit. B3)	0.3 mg (2%)
Pantothenic acid (B5)	0.338 mg (7%)
Vitamin B6	0.116 mg (9%)
Folate (vit. B9)	68 μg (17%)
Vitamin C	2 mg (2%)
Calcium	70 mg (7%)
Iron	0.7 mg (5%)
Magnesium	42 mg (12%)
Phosphorus	23 mg (3%)
Potassium	400 mg (9%)
Zinc	0.17 mg (2%)
Percentages are relative to US recommendations for adults. Source: USDA Nutrient Database

Cardoon stalks can be covered with small, nearly invisible spines that can cause substantial pain if they become lodged in the skin. Several spineless cultivars have been developed to overcome this, but care in handling is recommended for all types.

Cardoon requires a long, cool growing season (about five months), but it is frost-sensitive. It also typically requires substantial growing space per plant, so is not much grown except where it is regionally popular.

Gastronomy

While the flower buds can be eaten much as the artichoke, more often the stems are eaten after being braised in cooking liquid. The flower buds of wild cardoons are still widely collected and used in southern Italy and Sicily.^[9]

Cardoon leaf stalks, which look like large celery stalks, can be served steamed or braised, and have an artichoke-like flavour. They are harvested in winter and spring, being best just before the plant flowers.^[6] In the Abruzzi region of Italy, Christmas lunch is traditionally started with a soup of cardoon cooked in chicken broth with little meatballs (lamb or more rarely, beef), sometimes with the further addition of egg (which scrambles in the hot soup - called stracciatella) or fried chopped liver and heart^{[citation needed]}. Cardoons are also an ingredient in one of the national dishes of Spain, the cocido madrileño, a slow-cooking, one-pot, meat and vegetable dinner simmered in broth.

In the USA, it is rarely found in stores, but available in farmers' markets, where it is available through May, June, and July. The main root can also be boiled and served cold.^[10] The stems are also traditionally served battered and fried at St. Joseph's altars in New Orleans.

Other uses

Cardoons are used as a vegetarian source of enzymes for cheese production. In Portugal, traditional coagulation of the curd relies entirely on this vegetable rennet. This results in cheeses such as the Nisa (D.O.P.), with a peculiar earthy, herbaceous and a slightly citric flavour that bears affinity with full-bodied or fortified wines.^[11]

They are also grown as ornamental plants for their imposing architectural appearance, with very bright silvery-grey foliage and large flowers in selected cultivars.^[4]

Cardoon has attracted recent attention as a possible source of biodiesel. The oil, extracted from the seeds of the cardoon, and called artichoke oil, is similar to safflower and sunflower oil in composition and use.^[12]

Gallery

• 

  Young leaves

• 

  Inflorescence bud

• 

  Garden plant in bloom

• 

  Cultivated cardoons in Ágreda, Spain

• 

  Cardoon prepared in the Navarrese way

References

1. ^ ^{a b c d e} Sonnante, G., Pignone, D, & Hammer, K. (2007). The Domestication of Artichoke and Cardoon: From Roman Times to the Genomic Age. Ann. Bot. 100: 1095–1100. Full text.
2. ^ Malta's Native Flora
3. ^ ^{a b} Tela Botanica: Cynara cardunculus L. (in French)
4. ^ ^{a b c} Huxley, A., ed. (1992). New RHS Dictionary of Gardening. Macmillan ISBN 0-333-47494-5.
5. ^ Euro+Med PlantBase Cynara cardunculus
6. ^ ^{a b} Plants for a future: Cynara cardunculus
7. ^ Conservation of plant genetic resources: Swiss National Database
8. ^ Vilmorin-Andrieux, M. & Robinson, W. (1885/undated). The vegetable garden: Illustrations, descriptions, and culture of the garden vegetables of cold and temperate climates. English Edition. Jeavons-Leler Press and Ten Speed Press. 1920 edition in Internet Archive
9. ^ Pignone, D, & Sonnante, G. (2004).Wild artichokes of south Italy: did the story begin here? Genetic Resources and Crop Evolution 51 (6): 577-580. Abstract
10. ^ "Cardoon - General information". Michigan State University Extension. August 3, 1999. http://www.msue.msu.edu/msue/imp/mod01/01600689.html. Retrieved 2006-11-18. 
11. ^ "The Wine Spectator, The World's 100 Best Cheeses". 2008. http://www.winespectator.com. 
12. ^ "Plant Oils Used for Bio-diesel". BDPedia.com, the Biodiesel WWW Encyclopedia. http://www.bdpedia.com/biodiesel/plant_oils/plant_oils.html. Retrieved 2006-11-18.