Robert Indiana kept a series of illustrated journals during the late 1950s and 1960s, in which he discusses the development of his work as well as his daily life on Coenties Slip.

Indiana's journal page for March 11, 1959, includes sketches of four ginkgoes, each representing a different ginkgo painting that Indiana was working on. Each sketch has notes indicating the painting's colors, medium, and dimensions. The works range in size from 8 by 6 inches to 50¼  by 41 inches. The different color combinations are gold on red, orange on purple, white on dark blue, and white on blue. He describes that paintings as having been done in color, "in the flat, clean-contour manner." 

Indiana records stopping by Ellsworth Kelly's studio on his way to the Barnett Newman opening (Barnett Newman: A Selection, 1946-1952, at French and Company, Inc.), only to learn that he had missed it. He notes that Kelly had all kinds of new works, and that "his color is changing: rich combinations now outside the primaries." He also writes that Agnes Martin was recovering from illness but that Kelly had decided she was bad for him, refusing to go into her studio or let her into his

Indiana then records seeing the film The Roots of Heaven based on Kelly's recommendation, and bumping into him and two friends afterwards. He describes their evening out, and notes that it snowed.