Macdonald’s discovery of Lucite 44 (a painting medium that changes the consistency of paint) finally allowed him to work as fluidly in oil as he did in watercolour. It also increased his productivity. In January 1960, he opened a solo show at Dorothy Cameron’s Here and Now Gallery in Toronto. A few months later, in April, he had a semi-retrospective exhibition at the Art Gallery of Toronto—the first retrospective ever offered to a living artist who was not a member of the Group of Seven. Roberts Gallery, an important commercial gallery in Toronto, asked to represent him, and he was offered a summer teaching post at the University of Southern California. It was at this height of activity that Macdonald painted Growing Serenity (1960).