Pick up seeds to grow CU Boulder’s iconic red sunflower this Earth Day
The Cockerell red sunflower as seen on the CU Boulder campus
Your opportunity to grow the staggering, multi-foot tall, red sunflower has arrived. One Seed is back for the spring.
Stop by the University Libraries to pick up red sunflower seed packets on April 14 in honor of Earth Day from 2:00 p.m. - 4:00 p.m. at the East Entrance of Norlin Library. Seed packets will also be available at the Ask a Librarian desk in Norlin and each of the campus libraries’ service desks starting April 14.
One Seed began in 2021 and since then we have distributed over 4,000 seed packets to the community. The project explores the red sunflower’s historical ties to CU Boulder, and the scientific aspects of this unique plant.
With the success of the program, community members who’ve planted the red sunflowers in the past often return to pick up more seeds for their gardens.
“One of the most exciting things about One Seed is that people have begun to share their stories of growing red sunflowers with us,” said Abbey Lewis, STEM Engagement Librarian. “We get pictures and hear about gardening plans and learn whose flowers were the deepest red and whose got eaten by squirrels. It’s been such a fun way to have people engage with the Libraries and learn about the unique materials in our collections. It's reciprocal—we give the community a story from CU Boulder’s history and in turn, they share their own story with us.”
Planting tips from CU Boulder Horticulturist Christian Parker
Sunflowers can be easy to grow particularly if planted in the right conditions. However, for gardeners looking to increase their success rate, Christian Parker, horticulture and weed management supervisor in Outdoor Services offers some advice:
“Sunflowers grow best in full sun, however they can do reasonably well with at least 6 hours of morning sun or 4 hours of afternoon sun. They are quite happy in poor soil conditions, and will respond well in any Colorado soil, whether it’s been amended with compost/fertilizer or not. Although they are very drought tolerant, for the best and largest plants/blooms, I would recommend daily watering until they are about 2 feet tall, and then pulling back to 2 – 3 times a week watering schedule (depending on current temperatures). One important thing to consider is location. These plants have shallow roots, but also get to be ten feet in height. So finding a spot in an area that is protected from high winds will help ensure that they do not break off at the root.”
The origins of the red sunflower
In 1910, Wilmatte Porter Cockerell, a high school biology teacher, noticed a red sunflower growing in the wild across the street from her home in Boulder. Along with her husband, Theodore Dru Allison Cockerell, a professor at the University of Colorado Boulder, Cockerell transplanted the sunflower into her own garden.
The flower was a "sport," a spontaneous mutation resulting in morphological differences in a plant. With their backgrounds in the sciences, the Cockerells knew that sunflowers are unable to be fertilized with their own pollen, and so experimented in cross-pollinating the sunflower with others until the desired red color was visible in the flower's offspring.
The Cockerells were able to sell seeds carrying the red mutation to seed companies and were recognized at the 1915 Panama-Pacific International Exhibition for their work in cultivating the unique flowers. The many varieties of red sunflowers available all over the world today are believed to be descendants of the one carefully tended by the Cockerells in Boulder, Colorado.
The University Libraries Archives holds 60 linear feet of physical archival materials from the Cockerells, including the original red sunflower—now nearly a century old. Elements of the T.D.A. Cockerell Collection have been digitized and can be found via the CU Digital Library.