Family Brassicaceae. Broccoli is a member of the species Brassica oleracea, bred for their edible tree-like flower stalks, which are harvested before the florets open. Broccoli was developed in the northern Mediterranean in the days of the Roman Empire, in about the 6th century BCE. Broccoli comes in many forms, such as the most common type "calabrese", the sprouting broccoli, or the purple broccoli varieties. Lone Star Nursery grows them all!