Typical Galician Horrio with leaf vegetables growing in the foreground.
I thought these were "grelos" the leaves of the "nabo" (turnip) but I understand they are "col berza", similar to a Brussels sprout plant.
Grelos are the leaves of the nabo (turnip). The young leaves or shoots
of which are called "nabizas" and when the leaves have grown up and
the flowers are going to appear, they are then called "grelos".
thanks to Carlos B.