Developing a sand stabilizer that integrates rapid curing, mechanical robustness, and environmental adaptability remains a significant challenge for desertification control. Herein, we introduce a scalable and biocompatible hydrogel system guided by amino acid chemistry, in which l-serine serves as both a redox catalyst and multifunctional structural modulator. The resulting hydrogel, composed of methoxy poly(ethylene glycol) methacrylate (PEGMA), glycerol, and l-serine (PGL hydrogel), forms a dynamic hydrogen-bonded network with ultrafast gelation under ambient conditions. When applied to sand, the precursor rapidly cures within 50 s to form a cohesive and flexible surface layer that resists wind erosion at speeds up to 15 m s-1 without noticeable particle loss. The hydrogel maintains strong interfacial adhesion and structural integrity after 32 days of thermal aging and 32 freeze-thaw cycles, and remains stable across a wide pH range (pH 3-9). Plant cultivation experiments using mung bean and wheat confirm its excellent environmental compatibility, supporting germination and robust root development. This amino acid-mediated strategy provides an efficient, eco-friendly, and field-deployable solution for sand stabilization and ecological restoration in arid and degraded environments.