The invention provides methods for increasing the levels of bi-antennary mono- and fully galactosylated N-glycans, and for decreasing the levels of hybrid-type galactosylated N-glycans on glycoproteins produced in plants or plant cells. In addition, the invention provides methods for the production of heterologous glycoproteins with increased levels of bi-antennary mono- and fully galactosylated N-glycans, or decreased levels of hybrid-type galactosylated N-glycans in plants or plant cells.
