Brassica oleracea var. italica x alboglabra.
Broccolini is a another hybrid of B. olearacea cultivars that are in different groups.
The parents are in the Italica group (common broccoli) and the
Alboglabra group (Gai lan which is an Asian cultivar).
Plants, up to 80 cm high have many small heads of flower buds like broccoli but they are on longer stalks.