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Coffee grounds: the magic ingredient to ASU's newly lush flowerbeds

Vicente Solis (left) and Rigoberto Polanco
April 30, 2013

Flower beds throughout ASU's Tempe campus are looking lusher than ever, and many of the citrus trees and lawns are greener and healthier looking, thanks in part to an innovative program started by a couple of Grounds Services employees who also are ASU students.

With majors in sustainable engineering and urban horticulture, Vicente Solis and Rigoberto Polanco have been able to demonstrate that a cup or two of coffee can be just as beneficial to campus plants as it is to the rest of us.

For more than a year, Sollis and Polanco have been collecting more than 500 pounds a week of used coffee grounds, using them as a natural fertilizer and soil amendment around campus.

Their “Grounds for Grounds” program has saved the equivalent of about $10,000 in fertilizer costs and $900 in waste removal fees, and has diverted almost a ton of waste from the landfill monthly. It has greatly improved campus soil quality, while avoiding the negative environmental impacts of synthetic fertilizers.

Facilities Management Grounds Services has won an ASU President’s Award for Innovation for the program. The award recognizes ASU faculty and staff who have developed creative and inspiring projects that address one or more of the challenges before us.

“What prompted us was the need for fertilizer, specifically an organic fertilizer because we wanted to avoid synthetics,” says Solis. “The past years have been rough on the university’s budget, so instead of sitting around and waiting for things to bounce back so we could buy fertilizer, we found another means.

“The bulk of the waste is from the four Starbucks and the three cafes that serve Starbucks coffee on the Tempe campus. We worked with partners at Aramark and ASU Facilities Management to develop the program, placing 96-gallon green bins on the Memorial Union loading dock and behind Oasis Café. These bins are filled once a day by Starbucks employees.”

When that program proved successful, Aramark trained its employees at campus convenience stories to recycle coffee grounds, and the team also recruited the Biodesign Institute to begin coffee grounds collection in academic buildings.

Coffee grounds are a low-nitrogen, slow release fertilizer which can bring down the pH levels of the soil and improve the availability of nutrients for plant life, Solis says. Used at high enough quantities, they improve the soil structure over time and attract earthworms, which improve the soil even more.

By contrast, synthetic fertilizers cause metal accumulation in soils, deplete oxygen in run-off waters and increase levels of nitrogen oxide in the atmosphere. Grounds Services is focused on maintaining organic landscapes, and it has enlisted student involvement in the program through Greek Life and the ASU Chavez Program.

“Recycling food waste is an essential component of ASU’s goal to be a Zero Waste Campus,” says Solis. “We believe this is the first program on campus to do that.

“We’ve noticed a ‘greener’ difference in our flower beds. The beds are holding more moisture, and flowers are looking beautiful throughout campus. The citrus trees are showing similar results, and the lawns did green up during the time of our test period.”

The two also give credit to Gary Matyas, who has been appointed to be in charge of the flower crew, and to the rest of the Grounds Services employees who carry out the project. 

“Because of Gary’s knowledge, experience, and his willingness and initiative to implement the Grounds for Grounds program in his beds, he is responsible for making it a big success,” says Polanco. 

Polanco, 31, is a New York City native who chose an urban horticulture major because he loves working with plants and soil. Solis, 29, says he was drawn to engineering because he enjoys problem-solving. They have been working at ASU and attending classes part-time for years, and both hope to graduate in 2014.

The two, who also won a Pitchfork Award this spring for their project, pointed out that most Starbucks shops will provide 5-pound bags of used grounds to individuals interested in using coffee grounds as a fertilizer at home.