Vincent van Gogh, Sunflowers, January 1889. The Van Gogh Museum in Amsterdam.

Petals of Van Gogh’s Sunflowers Have Begun to Wilt, Researchers Say

Researchers have discovered that the petals and stems of Vincent van Gogh’s famous 1889 Sunflowers painting at the Van Gogh Museum in Amsterdam have begun to microscopically wilt, Nina Siegal of the New York Times reports.

Frederick Vanmeert—a doctoral candidate in the chemistry department at the University of Antwerp—confirmed that, while the effect cannot yet be seen with the naked eye, the colors of the pale yellow flowers have begun to change. He coauthored a technical study, published in the scientific journal Angewandte Chemie, which explains that the artist used a light-sensitive pigment and that soon the yellow bouquet may turn to an olive green.

The researchers collaborated with the museum in 2016. They analyzed the work through a chemical-mapping process called “macrosopic X-ray powder diffraction,” which allowed them to examine the painting without ever having to touch its surface, and discovered that Van Gogh had used three types of yellow pigments that were fairly new at the time. Vanmeert said that they were purchased by the tube and that two of the colors deteriorate after exposure to light.

Vanmeert also confirmed that the National Gallery in London is expecting to receive the same diagnosis for the version of Sunflowers exhibited within the institution. The findings follow a 2013 study that concluded that the artist also used a red pigment that fades to white, which is why his painting The Bedroom, 1888, seems to have blue walls. They were originally purple.

After learning of the problems with the yellow paint, the Van Gogh Museum said that its staff will monitor the work in which he used the color closely and will carefully consider how to best care for the piece.