Porous silicon (pSi) is an exciting nanostructured material poised to take center stage in the evolving biosensing effort for real-time detection applications. Sophisticated designs based on pSi platforms are currently utilized in biomedical diagnostics, environmental monitoring, veterinary and food quality control. The broad spectrum of applications is mainly ascribed to the fine tuning of the intrinsic characteristics, e.g., tunable optical and morphological properties, ease and speed of fabrication, high internal surface area and versatile surface chemistries, that render it as an ideal nanomaterial platform for label-free biosensing. The present overview focuses on the latest optical sensing schemes for monitoring agriculture related analytes.