‘Nano’ fertilizers will reduce problem of excess fertilizer and run-off in farming.
Tiny invention, big solution. Nano fertilizers prove as effective as conventional ones
Not only did nano fertilizers grow equally healthy crops as conventional fertilizers, researchers found they also released nutrients more slowly—and more efficiently.
By Emma Bryce
July 11, 2025 in Anthropocene magazine
Nano fertilizers can be just as good at growing crops as regular fertilizers—and potentially with less environmental impact, according to recent research. The new study adds to the accumulating evidence that a more sustainable agricultural future may lie in these minuscule feats of engineering.
One way of making fertilizers on the nanoscale involves producing microscopic granules of crop nutrients like nitrogen or phosphorus—usually smaller than 100 nano meters. The idea is that the smaller size of these particles enables easier absorption by plants, and therefore it’s possible to give plants a smaller and more targeted application of fertilizers. In theory, this means farmers could apply less fertilizer to the land overall—tackling the problem of excess fertilizer and run-off in farming.
But beyond the buzz about the technical feat of their creation, there has been relatively little research looking at how well nanofertilizers actually support crop growth compared to conventional fertilizers. This is a gap that the team of Italian researchers on the new study wanted to fill.
Their research focused on nanoparticles of iron-phosphate, phosphorus being a core nutrient in many conventional fertilizers. The team compared their nano fertilizer with ‘triple superphosphate’ or ‘TSP’, a widely-used chemical fertilizer that typically takes the form of chunky granules that are scattered over farmland. They tested each type of fertilizer on a batch of potted cucumber plants.
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Over the course of 28 days, they evaluated the growth of one set of pots that had been fertilized with conventional TSP feed, and another that was supplied with the nano fertilizer treatment.
Firstly and most importantly, the differently-treated plants showed no differences in the leaf area, root mass, chlorophyll content, or weight, when researchers dried out plant samples and compared them with one another after the experiment. “Plants fertilized with the nanoparticles grew just as well as those fertilized with triple superphosphate,” says Zeno Varanini, a professor of agricultural chemistry at the University of Verona, and lead author on the study, answering together with his colleague Anita Zamboni, an associate professor of agricultural chemistry at the university, and a co-author on the new research.
An even more compelling result emerged when the researchers ran something called the Olsen P test, a sensitive measure that is used to detect levels of phosphorus in the soil. “Our results indicate that the nanoparticles released phosphorus into the soil more slowly than TSP and in different chemical forms—forms that were likely underestimated by the Olsen method but were still available to plants,” the research duo says.
Possibly, this indicates that the nano fertilizer are able to support plants by providing a more consistent, steady supply of nutrients, compared to the conventional fertilizers that by comparison tend to release all their nutrients into the soil in one go—which increases the risk of run-off and nutrient pollution. “The overall picture suggests that in the long term, these nanomaterials may perform better due to their slower release profile compared to conventional fertilizers,” Varanini and Zamboni say.
Another surprise finding was that the nano fertilizer-treated pots had a distinct soil profile with a unique constellation of bacteria and fungi. This reveals possibly positive interactions between nano fertilizers and soil and root microbes, which are known to play a role in aiding plants’ absorption of phosphorus and other nutrients from the soil.
These are strands of the work that require further investigation. But for now it appears the researchers are onto something promising, having identified a tool that could potentially help to reduce the gargantuan global problem of nutrient pollution from farms.
“Research into nanomaterials as agricultural fertilizers is still in its early stages,” Varanini and Zamboni say. That said, the duo note that based on their work, an Italian company has already developed a line of nano fertilizers that is now being used in agriculture. “In general, the company’s field trials have shown some benefits, especially a reduced need for product compared to conventional fertilizers.”
Zamboni et. al. “A novel nanosized FePO4 fertilizer is as effective as triple superphosphate in sustaining the growth of cucumber plants.” Pedosphere. 2025.