In 1958, O'Keeffe painted Ladder to the Moon. The painting shows a handmade wooden ladder suspended in the turquoise sky. In the background are the pitch-black Pedernal Mountains and a pearl-colored half-moon. This painting was very similar to a picture taken of O'Keeffe and her surroundings at Ghost Ranch. In the picture, a large wooden ladder is leaned against an outer wall of a patio from where it rises up into the sky with the Pedernal Mountains in the background. Some say her immediate surroundings at Ghost Ranch were the inspiration for this piece of art. Others interpret the painting as a religious work. In Pueblo culture, the ladder is used to symbolize the link between the Pueblos and cosmic forces. The fact that the ladder is pointed up in the sky may represent the link between nature and the cosmos.
In her biography of O'Keeffe, Roxanna Robinson describes this work as somewhat of a self-portrait of the artist in her later years, highlighting the transitory nature of the stage of life she was at when she painted it. She writes,
The images are all of transition: the ladder itself implies passage from one level to another; the moon is cut neatly in half by the bold slicing light, halfway between full and new; and the evening sky is in flux, still pale along the line of the horizon, shading into deep azure night at the top of the canvas. ”