Farmers in the Democratic Republic of Congo (DRC) village of Shasha – which is located in the Masisi region just southwest of Goma – are making use of their neighbours’ urine to increase their crop yields.
According to Scientific America, urine is full of nutrients plants need to thrive, such as nitrogen, potassium, and phosphorus – which are also among the strongest minerals found in traditional chemical fertilisers.
“The nutrients in urine are also in just the right form for plants to drink them up,” said Håkan Jönsson to Scientific American. He has conducted many studies into urine recycling for the Swedish University of Agricultural Sciences. “Food gives us nutrients like nitrogen as parts of complex organic molecules, but our digestive system strips them down into the basic mineral form that plants need – so we have done half of the job.”
In Shasha, farming is one of the main activities found in the village, but due to land degradation and climate change, the soils there are becoming less arable. This has had a knock-on impact with the local population and harvesting abilities, causing the village to become food insecure. Previously, Shasha was one of the DRC’s most abundant agricultural communities and used to supply the city of Goma with basic necessities.
This drove many of the farmers in the village to offer their neighbours financial compensation for their urine, and according to farmers, a month’s worth of urine is enough to “kill any insect that may attack the plant”.
Water makes up 95% of urine. The remaining 5% is made up of minerals, salts, hormones, and enzymes, as well as urea (about 2.5%). It is a blood byproduct, and is non-toxic despite having some bodily waste.
How to apply urine to plants
“It is too strong to be used neat on most plants and should be diluted. Dilute one part fresh urine to 10 – 15 parts water for application on plants in the growth stage. Dilute one part fresh urine to 30 – 50 parts water for use on pot plants, which are much more sensitive to fertilisers of any kind,” states the Permaculture Research Institute.
“Even when diluted, your plants don’t need daily applications, and it’s best used on plants that need lots of nitrogen, such as corn and squash, tomatoes, and cucumbers during their fruit-bearing stage. You can also use it to remedy nitrogen deficiencies. Signs of nitrogen deficiency include yellow or pale green leaves.”
There’s a risk of adding too much nitrogen, which might result in bushy, green plants that attract pests and produce little fruit. Curled leaves are a sign of too much nitrogen.
“Urine can be applied directly to the compost pile. As it’s very high in nitrogen, it should be added to plenty of carbon-rich materials, like dry leaves, sawdust, straw, and cardboard. Urine can act as a starter for compost, encouraging the decomposition process. Undiluted urine can also be applied directly to heavily mulched soils serving the same function as above. The mulch should be thick enough to absorb the urine before it can make contact with plant roots,” the institute added.
Underestimated and under-utilised
There are reports of farmers across the continent making use of urine as an alternative to traditional chemical pesticides, with some starting as early as 2007 in Uganda.
“The promotion of inorganic fertiliser is a dominant strategy among governments and international development organisations to tackle low soil fertility. However, for the large majority of farmers in sub-Saharan Africa, such initiatives have had limited effects due to high costs and limited access,” said Elina Anderson, a sustainability researcher for Lund University Centre for Sustainability Studies (LUCSUS).
“Human urine is a valuable, yet underestimated and under-utilised resource for plant fertilisation that has been used in agriculture since ancient times, not least in intensive farming systems in various parts of Asia.”