(Wikipedia) Fore-runners to modern Brussels sprouts were likely cultivated in ancient Rome. Brussels sprouts as we now know them were grown possibly as early as the 1200s in what is now Belgium. The first written reference dates to 1587. During the sixteenth century they enjoyed a popularity in the southern Netherlands that eventually spread throughout the cooler parts of Northern Europe.
Brussels sprouts grow in temperature ranges of 7 to 24°C (45 to 75°F), with highest yields at 15 to 18°C (60 to 65°F). Plants grow from seeds in seed beds or greenhouses, and are transplanted to growing fields.. Fields are ready for harvest 90-180 days after planting. The edible sprouts grow like buds in a spiral array on the side of long thick stalks of approximately 2-4 feet in height, maturing over several weeks from the lower to the upper part of the stalk. Sprouts may be picked by hand into baskets, in which case several harvests are made of 5-15 sprouts at a time, by cutting the entire stalk at once for processing, or by mechanical harvester, depending on variety. Each stalk can produce 1.1 to 1.4 kg (2 1/2 to 3 pounds), although the commercial yield is approximately 0.9kg (2 pounds) per stalk..
Brussels sprouts are among the same family that includes cabbage, collard greens, broccoli, kale, and kohlrabi. They contain good amounts of vitamin A, vitamin C, folic acid and dietary fibre. Moreover, they are believed to protect against colon cancer, due to their containing sinigrin. Brussels sprouts are cruciferous.