The Crop-Protector Grain Monitoring System consist of a suite of sensors for the monitoring of temperature, moisture, and spoilage (CO2) using digital technology and automated controls to optimize the condition of grain stored in silos, flat storage warehouses, and piles. The system includes: temperature sensor cables, temperature sensor lances, moisture sensor cables, and a weather station-all portable for installing in one's particular grain storage facility. The data collected by these sensory instruments can be sent to one's desktop or laptop PC, smart phone, or other device with the Crop-Protector software.