UoH Scientists Turn Geranium Waste Into Soil-Boosting Biochar

In a breakthrough for sustainable agriculture, researchers at the University of Hyderabad (UoH) have developed an innovative method to convert waste geranium leaves - usually discarded by the essential oil industry - into high-quality biochar that significantly improves soil fertility and plant growth.

The study, published in Biomass and Bioenergy (Elsevier, Nov 2025), was jointly led by Prof Appa Rao Podile of the School of Life Sciences and Prof Dr V V S S Srikanth of the School of Engineering Sciences and Technology.

Their interdisciplinary team engineered an efficient process to turn aromatic crop residues into a carbon-rich soil amendment.

The geranium-leaf biochar showed 65% carbon content, alkaline properties, and essential minerals including calcium, potassium and magnesium. When applied to soil, it noticeably enhanced the growth and nutrient uptake of rosemary plants, demonstrating its agricultural value.

The process is also cost-effective, requiring only 9 kWh per batch, making the biochar cheaper than many commercial variants, and offers a scalable model for waste valorisation.

The researchers say the innovation supports soil restoration, carbon sequestration, and India's emerging circular bioeconomy.

Prof Podile said that the study shows "how industrial waste can become a sustainable soil enhancer", while Prof Srikanth said that the engineering-life sciences partnership enabled a "holistic, environmentally impactful solution".

The project was supported by DBT, DST-FIST (Department of Science and Technology - Fund for Improvement of S&T Infrastructure) and IoE-UoH (Institution of Eminence program).