Farmers on the slopes of Mount Etna in Sicily have begun using volcanic ash as a natural fertiliser, turning a longstanding nuisance into an agricultural asset. Andrea Passanisi, a tropical and citrus fruit producer in Giarre, applies the ash on his 100-hectare farm, reducing his reliance on chemical fertilisers. 'It allows us to use fewer chemicals, which makes fertilising cheaper and more sustainable,' he says.
The shift follows a five-year University of Catania project that explored the ash's potential across sectors, including agriculture, construction and water purification. Lead researcher Paolo Roccaro explains that after 2011, increased explosive eruptions made a systemic solution essential. The ash, rich in iron, aluminium and silica, also helps drain excess water from soil, as noted by vineyard owner Emilio Sciacca in Linguaglossa.
Despite its benefits, regulatory barriers hinder commercial use. European law classifies collected volcanic ash as municipal waste (EWC 20 03 03), requiring disposal at authorised landfills at a cost of €300 per tonne. Recycling could reduce this to €30 per tonne, but no registered companies yet exist to collect and refine the ash for reuse. Regional guidelines published in 2024 aim to promote the practice, but adoption remains slow.
In Iceland, farmers have also discovered the value of volcanic ash. After the 2010 Eyjafjallajökull eruption, which caused widespread disruption, some farmers now use ash from subsequent eruptions to improve soil fertility. The ash enriches volcanic soils with essential minerals, mirroring the Sicilian experience.
Roccaro hopes the project will inspire systemic change: 'The goal is to instil the idea that this alternative approach can work, to make its systemic reuse more palatable in the near future.' For now, farmers like Passanisi and Sciacca are leading the way, embracing what Sciacca calls 'a gift that falls from the sky.'
