The title compound, C₂₆H₄₂O₉·1.5H₂O, was extracted from the leaves and flowers of Ageratina vacciniaefolia, a Colombian native plant, which is called ‘chilca’ by locals. The molecule consists a kauranol group connected to a glucopyranosyl group by an O-atom bridge adjacent to a β-type anomeric center. In the crystal structure, intermolecular O–H⋯O hydrogen bonds link molecules to form a three-dimensional network. One solvent water molecule lies on a crystallographic twofold axis, while another is disordered over three sites with equal occupancies.