Self-Irrigation and Slow-Release Fertilizer Hydrogels for Sustainable Agriculture

Given the critical need for more efficient water and nutrient utilization to optimize crop yields, effective strategies in water and nutrient management are essential. The development of a self-irrigation and slow-release fertilizer hydrogel (SISRH) represents a promising approach. SISRH, a hydrogel with hygroscopic polymer chains interpenetrated by a thermoresponsive network, enhances plant growth through controlled yet self-sustained water and nutrient delivery. The hydrogel demonstrates diurnal functionality: it absorbs water vapor at night and releases it during the day due to a phase transition in the polymer, with incorporated calcium chloride (CaCl₂) further improving hygroscopic properties and controlled nutrient release. SISRH facilitates a slow-release of nutrients and can achieve ∼40% water savings, significantly reducing the need for frequent irrigation and ensuring robust crop development. The integration of SISRH in soil offers a promising solution to meet the pressing needs of water scarcity and efficient nutrient uptake in modern sustainable agriculture.