Technical Abstract: Winter cover crops (WCC) are important universal tools that can be used to conserve environmental sustainability. In general, the term 'winter cover crop' is used to describe a cover crop grown to protect the soil during the winter fallow period. A cover crop can be used even during summer, especially in the tropics. A cover crop can also be used on a more permanent basis during the entire year, for example a cover crop planted between papaya trees Winter cover crops serve as a soil conservation tool by sheltering the soil against wind and water erosion and reduce the off-site transport of soil particles, nutrients and soil organic matter by erosive processes. Winter cover crops improve air quality by reducing the aerial transport of light soil particles and chemicals associated with them due to wind erosion. Winter cover crops improve water quality and conservation by increasing N use efficiency, which reduces the potential for NO3-N leaching. Winter cover crops serve as 'catch crops' to scavenge NO3-N from the soil profile. Leguminous winter cover crops can fix atmospheric N2 and serve as green manures. Among other benefits of growing cover crops are weed suppression, carbon sequestration, and integrated pest management. WCC are a viable tool for soil and water conservation.