These plants are native to the eastern Mediterranean, and were widely grown by the Greeks and Romans who imported them from Northern Africa. They have been cultivated in England since the sixteenth century, where it has always been considered an aristocratic vegetable. A favorite of Henry VIII partly because it was considered an aphrodisiac. His head gardeners took great care cultivating the plants so there would be continuos harvest throughout the summer.
Globe artichokes are different than most vegetables because it is the immature flowers that are eaten. When they are older only the fleshy bases of the bracts (phyllaries) and the choke, the thickened receptable at the base that are soft enough to eat. The tender young flower stalks and leaves are also delicious.
Globe artichokes belong to the thistle side of the compositae family with more wildling varieties having prickly phyllaries and slightly prickly leaves. They are closely related to the cardoon. The plants are perennial. When the flowers open they resemble huge thistles and are striking in dried flower arrangements.
Modern varieties are bred to produce a large succulent flower without spines on the phyllaries. Some seed raised plants can be a bit spiny so it is worth propagating new plants from a non-spiny form when you find them. Green Globe Improved is a good seed grown variety, with a small number of spiny seedlings. Violetta, is an Italian purple-budded variety, the buds are elongated and are wonderful for pickling when the buds are young and tender. Purple Ruscoff is a similar variety from Brittany, with lovely purple highlights on the phyllaries.
Artichokes thrive in warm light soils in Northern Europe, but will often die out in cold heavy soils. If the region is hot they will tolerate a heavier soil and a bit of midday shade. The largest artichoke growing regions are in france in Brittany, near Treguier, where they have been cultivated since 1508, and in Italy on the coastal plains near Brindisi. Both of these regions have light soils and a mild winter climate. Artichokes in the home garden will do best in a warm, sheltered bed. With rich well drained soil and plenty of humus and compost. Set out young plants or cuttings from side shoots in the early spring. Space them about a foot apart in double rows. These plants should grow quickly and need to be side dressed several times early in the season with an organic fertilizer rich in nitrogen. Espoma dried blood is excellent for this. Some of the plants will sprout small flowers in late fall their first growing year. These should be cut to encourage your plants to form side shoots. You can protect established plants from extreme cold or sudden hard frosts by putting a thick layer of straw around the base of the plants. Every spring apply about 2- 3″ of compost or well-rotted manure and mulch for the growing season. Older plants should be replaced with young seedlings every third year. Artichokes are usually pest and disease free. The only problem you might encounter is with lettuce root aphids. This usually happens to young plants that are stressed from weather extremes or not enough organic mater in the soil. If your plants are affected remove the worst plants and use an organic insecticide soap to drench the soil around the other plants. Repeat several times until the problem is cleared up.