Biodegradable Materials for Controlled-Release Fertilizers: A Comprehensive Review with a Focus on Applications in Türkiye

The excessive use of chemical fertilizers leads to both economic losses and environmental degradation, as a significant portion of applied nutrients is lost via leaching, volatilization, or attachment to soil organic matter. To overcome these challenges, controlled-release fertilizers (CRFs) were developed. However, conventional synthetic CRFs can have adverse effects on soil health. In response to these limitations, biodegradable-CRFs (BD-CRFs) have emerged, using natural or bio-based polymers to provide controlled-release of nutrients without leaving harmful residues. This review examines BD-CRFs as sustainable alternatives to synthetically-derived CRFs and specifically discusses CRF applications under Türkiye’s diverse agricultural and climatic conditions. Unlike previous reviews, it summarizes the latest developments in BD-CRF technologies, emphasizes advancements over state-of-the-art synthetic CRFs, and lists the environmental advantages and unresolved issues. The findings suggest that BD-CRFs can increase nutrient use efficiency, reduce fertilizer loss, boost crop yields, and mitigate the risk of water pollution and soil erosion. Recent developments in BD-CRF technologies have also demonstrated their potential to reduce the environmental footprint associated with conventional CRFs. Despite this progress, challenges related to production cost, limited scalability, and regional adoption remain. Overall, BD-CRFs represent a promising pathway to balance agricultural productivity and environmental sustainability, and their effective implementation could have significant impacts by improving future research, guiding agricultural policy, and ensuring the sustainable management of fertilizers.