Biodegradable Self-Regulating Fertiliser Beads

Chemical fertilisers use pose significant environmental risks, primarily the soil and water. The development of a biodegradable, self-regulating fertiliser from domestic waste is essential for boosting crop productivity while mitigating the excessive nutrient release problems commonly associated with chemical fertilisers. This study developed a biodegradable slow-release fertiliser and its vessels to promote an environmentally friendly solution which supports the United Nations’ SDGs 12, 14, and 15. Calcium carbonate, nitrogen, and potassium were extracted from eggshells, tea grounds, and banana peels, respectively, and bound with aloe vera gel and cornstarch for slow nutrient release. The formed beads withstood an average of 755 g load pressure. In a 3-day trial, onion plants treated with the biofertiliser showed 47.8% leaf growth and one new leaf, outperforming chemical fertilisers (22.2%, no new leaf). At Technology Readiness Level 6, further studies will assess soil decomposition and effects on root development.