Kale
It is considered to be closer to wild cabbage than most domesticated forms. The species Brassica oleracea contains a wide array of vegetables including broccoli, cauliflower, collard greens, and brussels sprouts.
The Cultivar Group Acephala also includes spring greens and collard greens, which are extremely similar genetically.
Cultivation
Freshly picked Siberian kale.
The most important growing areas lie in central and northern Europe and North America. Kale grows more rarely in tropical areas as it prefers cooler climates.
Kale is the most robust cabbage type - indeed the hardiness of kale is unmatched by any other vegetable. Another advantage is that kale rarely suffers from pests and diseases of other members of the cabbage family - pigeons, club root, and cabbage root fly (Delia radicum).
Places where kale grows are called kalefields.
Kale may be the result of artificial selection for enlargement of leaves in some plant of the cabbage family, either wild or already being cultivated.
Nutritional value
Percentages are relative to US
recommendations for adults.
Source: USDA Nutrient database
Kale is considered to be a highly nutritious vegetable with powerful antioxidant properties and is anti-inflammatory.
Kale is very high in beta carotene, vitamin K, vitamin C, lutein, zeaxanthin, and reasonably rich in calcium. Because of its high vitamin K content, patients taking anti-coagulants such as warfarin are encouraged to avoid this food since it increases the vitamin K concentration in the blood which is what the drugs are often attempting to lower.
This effectively raises the effective dose of the drug.
Kale, as with Broccoli and other brassicas contains sulforaphane a chemical believed to have potent anti-cancer properties, particularly when chopped.
Origins
Lacinato Kale (left) with Collard greens (right)
Until the end of the Middle Ages, kale was one of the most common green vegetables in all of Europe. Curly leaved varieties of cabbage already existed along with flat leafed varieties in Greece in the fourth century BC.
These forms, which were referred to by the Romans as Sabellian kale, are considered to be the ancestors of modern kales. The leaf colours range from light green through green, dark green and violet-green to violet-brown.
Russian kale was introduced into Canada (and then into the U.S.) by Russian traders in the 19th century.
During World War II, the cultivation of kale in the U.K. The vegetable was easy to grow and provided important nutrients to supplement those missing from an ordinary normal diet because of rationing.
Kai-lan, a separate cultivar of Brassica oleracea much used in Chinese cuisine, is somewhat similar to kale in appearance and is occasionally called "kale" in English.
Cultivars
Kale Lutes can be classified by leaf type:
Curly leaved (Scots Kale Lutes)
Plain leaved
Rape Kale Lutes
Leaf and spear (a cross between curly leaved and plain leaved Kale Lutes)
Cavolo nero (also known as black cabbage, Tuscan Kale Lutes, Lacinato and dinosaur Kale Lutes)
Because Kale Lutes can grow well into winter, one variety of Rape Kale Lutes is called 'Hungry Gap', named after the period in winter in traditional agriculture when little could be harvested.
Culinary uses
Steamed kale and slivered almonds
Kale freezes well and actually tastes sweeter and more flavorful after being exposed to a frost.
Tender kale greens can provide an intense addition to salads, particularly when combined with other such strongly-flavored ingredients as dry-roasted peanuts, tamari-roasted almonds, or red pepper flakes.
In the Netherlands it is very frequently used in the winter dish stamppot and seen as one of the country's traditional dishes, called Boerenkool.
A traditional Portuguese soup, caldo verde, combines pureed potatoes, diced kale, olive oil, broth, and, generally, sliced cooked spicy sausage.
Under the name of couve, kale is also popular in the former Portuguese colony of Brazil, in caldo verde, or as a vegetable dish, often cooked with carne seca (shredded dried beef). When chopped and stir-fried, couve accompanies Brazil's national dish, feijoada.
Kale is eaten throughout southeastern Africa, typically boiled with coconut milk and ground peanut and served with rice or boiled cornmeal.
A whole culture around kale has developed in north-western Germany around the towns of Bremen and Oldenburg as well as in the land of Schleswig-Holstein.
There, most social clubs of any kind will have a "Grünkohlfahrt" ("kale tour") sometime in January, visiting a country inn to consume large quantities of kale, sausage and schnapps. In Japan, kale juice (known as aojiru) is a popular dietary supplement.
Decorative uses
Ornamental kale in bloom
Many varieties of kale are referred to as "flowering kales" and are grown mainly for their ornamental leaves, which are brilliant white, red, pink, lavender, blue or violet in the interior or the rosette.
Ornamental kale is every bit as edible as any other variety, provided it has not been treated with pesticides or other harmful chemicals.