Peter H. Raven, the George Engelmann Professor of Botany Emeritus in Arts & Sciences at Washington University in St. Louis, died Saturday, April 25, 2026. He was 89.
One of the most influential botanists of the 20th century, Raven helped define the international conversation around biodiversity and the urgent need to protect the planet. Named a "Hero for the Planet" by Time magazine in 1999, Raven championed research around the world to preserve endangered plants and was a leading advocate for conservation and a sustainable environment.
"Peter left an indelible mark on WashU, the St. Louis community and the field of botany as a whole," said Feng Sheng Hu, the Richard G. Engelsmann Dean of Arts & Sciences. "Even as a professor emeritus, he remained a strong supporter, thought partner and friend to many of us in Arts & Sciences. His insights and generosity will be greatly missed."
Raven joined the WashU Department of Biology in 1971, the same year he assumed the role as director of the Missouri Botanical Garden. He was installed as the George Engelmann Professor of Botany in 1976.
He served as president of the garden for nearly four decades, helping shape it into one of the world's leading centers for botanical science, conservation and education. He retired from both positions in 2010 and served as president emeritus and consultant through 2014.
Raven taught and mentored generations of students. He was chair or a member of the committees of more than 35 PhD students, many of whom went on to their own distinguished careers, according to his former biology colleague and friend, Barbara A. Schaal, the Mary-Dell Chilton Distinguished Professor at WashU.
"Peter's contribution to the scientific workforce locally, nationally and internationally is a profound and enduring influence on the plant sciences," Schaal said.
Raven was the recipient of numerous prizes and awards, including the MacArthur Fellowship and the U.S. National Medal of Science, the country's highest award for scientific accomplishment.
He was a member of President Bill Clinton's Committee of Advisors on Science and Technology. He also served for 12 years as home secretary of the National Academy of Sciences and was a member of the academies of science in Argentina, Brazil, China, Denmark, India, Italy, Mexico, Russia, Sweden, the United Kingdom and several other countries.
His final publication, an autobiographical memoir, "Driven by Nature," published in 2021 by Missouri Botanical Garden Press, chronicled his life across multiple continents and decades advocating for conservation and biological education.
Raven is survived by his wife, Patricia Duncan Raven; four children, Alice Raven (Sam Stuhlman), Liz Raven McQuinn (Daryl McQuinn), Francis Raven (Carolyn Kousky), and Kate Raven (Katrina Schaffer); and four grandchildren Noah, Nate, Louisa and Rosvita.
