ANN ARBOR, Mich. (AP) — A pair of University of Michigan researchers are putting the “pee” in the peony.
On the contrary, they pee ON peonies.
Environmental engineering teachers Nancy Love and Krista Wigginton are regular visitors to the school’s Nichols Arboretum in Ann Arbor, where they applied urine-based fertilizers to the heirloom peony beds before the annual spring blooms of the flowers.
This is all part of an effort to educate the public about their research showing that applying nutrient-rich urine-derived fertilizers could have environmental and economic benefits.
“At first we thought people might be hesitant. You know, that could be weird. But we really experienced very little of that attitude,” Wigginton said. “Usually people think it’s funny at first, but then they understand why we’re doing it and they support it.”
Love co-authored a study published in the journal Environmental Science & Technology that found that diverting and recycling urine resulted in significant reductions in greenhouse gas emissions and energy.
Urine contains essential nutrients such as nitrogen, potassium and phosphorus and has been used as fertilizer for crops for thousands of years.
Love said collecting human urine and using it to create renewable fertilizer — part of what she calls the “circular nutrient economy” — will lead to greater environmental sustainability.
Think of it not so much as recycling, but as “pee-cycling,” Wigginton said.
“We were looking for terms that would echo, but get the idea across, and ‘pee’ seems to be the one that stuck,” she said.
As part of a $3 million grant from the National Science Foundation in 2016, Love and Wigginton not only tested advanced urine treatment methods, but also investigated people’s attitudes about the use of urine-derived fertilizers.
This is what brought them to the much-loved Peony Garden campus, which contains over 270 historic 19th and early 20th century cultivated varieties representing American, Canadian and European peonies of the time. The garden contains almost 800 peonies when full and up to 10,000 flowers when in full bloom.
Love and Wigginton plan to spend the weekends in May and June chatting with visitors. An important lesson they learned concerns the precision of language.
“We used the term, ‘pee on the peonies.’ And then that gets people’s attention and then we can talk to them about nutrient flows and nutrient efficiency in our communities and how to be more sustainable,” Love said. “It turns out that some people thought it was permission to drop their drawers and pee on the peonies.
“So this year we’re going to use ‘pee for peonies’ and hopefully we won’t have that confusion.”
The urine-derived fertilizer that researchers use these days comes from Vermont. But if all goes as planned, they will distribute local fertilizers next year.
A separate bowl toilet in an engineering building on campus is designed to send solid waste to a treatment plant while directing urine to a holding tank downstairs. Urine diverted from the toilet and urinal was to be treated and possibly used to create fertilizer, but the COVID-19 pandemic forced the school to halt collection efforts.
In the meantime, the facility is undergoing an upgrade to its freezing concentrator and the addition of a new, more energy-efficient pasteurizer, both developed by Vermont’s Rich Earth Institute.
“The idea is to ride the bike within a community, so we want to take the urine from that community and apply it within that community,” Wigginton said.