Pasadena Water and Power Partners With Poly for First Hügelkultur School Site

Sustainability is a priority of Polytechnic School, and on November 9, Poly partnered with Pasadena Water and Power (PWP) to bring a new conservation technique to campus. Hügelkultur is a regenerative landscaping technique that mimics what happens in nature and builds fertile soil while also conserving water. The German name means hill or mound culture. Poly is the first school site to partner with the city of Pasadena to build a hügel.

PWP has identified Hügelkultur as a way to save water in urban landscapes. The city sponsored the workshop and has contracted Studio Petrichor, a local landscape architecture firm, to lead it. The partnership began nearly two years ago when Studio Petrichor's Leigh Adams visited Poly for educational talks about nature-based landscaping. Inspired by the presentation, the Upper School Closing the Loop club reached out to the city to pursue bringing the Hügelkultur project to campus. Thanks to the initiative of Poly students, the partnership has tangibly changed our school campus and taught our community the importance of conservation.

“As students, having a Hügelkultur and a project of this scale on Arden, a center of our community, is an opportunity to have a legacy and see a living, breathing piece of nature on our campus,” said Ollie A-J ’25. “It’s an opportunity to connect with the future and influence the land in a lasting way.”

On November 9, more than 40 attendees, including Poly K-12 students, faculty, staff, current parents and guardians, alumni, and alumni parents gathered for the build. The group built a planting bed on Arden Lawn on South Campus with layers of organic materials such as cut logs, mulch, twigs, grass, and soil to create a hügel. The project also included stormwater capture from a rooftop that will be piped to a water infiltration basin next to the mound. 

“Building the Hügelkultur is a one day of building something with friends and community, but it gives us years of benefit,” said Zaph C. ’25. “The most impactful moment of building it was when a teacher brought their young son, and we danced on the Hugel together, it was incredible to see that joy.”

As the woody organic material in the mound decays, it will soak up water like a sponge, providing water and nutrients to the native plants on the hügel and the nearby trees. Poly’s grounds, like many other urban sites, have a lot of compacted soil where water does not penetrate, and plants and grass cannot establish roots. The project demonstrates how individuals can create fertile soil using nature-based techniques and establish an outdoor learning lab for science classes.

PWP was awarded a grant from the Bureau of Reclamation to build hügels at several city sites and educate residents on using a nature-based technology to build healthy soil and save water in our landscapes. So far, this includes sites at the corner of Coniston Road and Arroyo Boulevard, in the Arroyo Seco adjacent to the Gabrielino Trail, and at the northern end of the Sierra Madre median.

“With so many schools in Pasadena, there is a wonderful opportunity for schools to learn about the benefits of hügels and be inspired to build them in their school landscape. We hope that this project at Poly can be a resource for schools and that the process of how this was achieved can be shared across the education community,” said Ursula Schmidt, PWP's Water Conservation Program Manager. 

Poly Upper and Middle School students have been learning about the unique biodiversity benefits of native plants and have been encouraging the school to transition to more native landscaping. Special thanks to the local tree trimmers who partnered with us and donated materials to make this project possible, Phil and Sons, Phil’s Arbor Care, Steven Tepe landscaping, and the city’s urban forestry division. With climate change accelerating biodiversity loss, rewilding Poly's campus with native plants is another way to boost biodiversity, providing critical habitat for pollinators and supporting the school’s natural landscape for future generations.