Born in Dublin and raised in Vancouver, Gretta has completd formal studies in fine art in Canada (BFA, University of Concordia, Montreal) and Spain (MFA, Universidad de Barcelona). She has also studied fresco painting at the Universidad de Lleida in Spain and painting at the Emily Carr College of Art and Design in Vancouver. She has studied independently at the Prado in Madrid, Spain; The Louvre in Paris, France; and the British Museum in London, England.

The study of art through its creation is her lifelong passion and pursuit.