‘Pee for the peonies’: researchers say urine fertilizers encourage blooms – and there’s never a shortage
A pair of University of Michigan researchers are putting the “pee” in peony. Rather, they’re putting pee on the vivid spring blooms.
Environmental engineering professors Nancy Love and Krista Wigginton are regular visitors to the Ann Arbor school’s Nichols arboretum, where they have been applying urine-based fertilizer to the heirloom peony beds ahead of the flowers’ annual spring bloom.
It’s all part of an effort to educate the public about their research showing that applying fertilizer derived from nutrient-rich urine could have environmental and economic benefits.
“At first, we thought people might be hesitant. You know, this might be weird. But we’ve really experienced very little of that attitude,” Wigginton said. “In general, people think it’s funny at first, but then they understand why we’re doing it and they support it.”
Love is co-author of a study published in the Environmental Science & Technology journal that found urine diversion and recycling led to significant reductions in greenhouse gas emissions and energy.
Urine contains essential nutrients such as nitrogen, potassium and phosphorus and has been used as a crop fertilizer for thousands of years.
Love said collecting human urine and using it to create renewable fertilizers will lead to greater environmental sustainability.
Think of it not so much as recycling, but “pee-cycling”, Wigginton said.
As part of a $3m grant from the National Science Foundation awarded in 2016, Love and Wigginton have been testing advanced urine-treatment methods and investigating people’s attitudes about the use of urine-derived fertilizers.
That is what brought them to the much-loved campus peony garden, which contains more than 270 historic cultivated varieties from the 19th and early 20th centuries representing American, Canadian and European peonies of the era.
“We have used the term, ‘pee on the peonies’. And then it grabs people’s attention and then we can talk to them about nutrient flows and nutrient effi
ciency in our communities and how to be more sustainable,” Love said.
“It turns out some people thought that that was permission to drop their drawers and pee on the peonies.
“So, this year, we’re going to use ‘pee for the peonies’ and hope that we don’t have that confusion.”
The urine-derived fertilizer the researchers are using these days originated in Vermont. But if all goes according to plan, they’ll be doling out some locally sourced fertilizer next year.