|Cardoons are a relative of the artichoke, and require much the same cultural conditions and care.
Plant indoors about 8 weeks before the soil warms, and then harden off and transplant shallowly outside. Space the plants 24 inches apart in rows 3 feet apart. If you want your cardoons to produce perennially, cut the stalks to 8 inches in early winter, and bury with straw. Next years' crop will be rooted offshoots of these parent plants.
Harvest: While growing, blanch the stalks by wrapping them in newspaper and tying with twine. The leaves can be eaten fresh like celery, or cooked.