What is one effective method to reduce nutrient leaching through sandy soil?

Adding organic matter to sandy soil is an effective method to reduce nutrient leaching primarily because organic matter enhances the soil's ability to retain water and nutrients. Sandy soils have larger particle sizes and greater drainage capacity, making them prone to leaching, where nutrients are washed away from the root zone before plants can take them up.

Organic matter improves the soil structure by creating a network that can hold moisture and bind nutrients more effectively. It increases the cation exchange capacity (CEC), allowing the soil to retain positively charged nutrients that might otherwise leach away. Furthermore, organic matter contributes to the microbial community in the soil, which plays a crucial role in nutrient cycling and availability.

In contrast, increasing fertilizer application or applying fertilizers at any time could potentially exacerbate nutrient leaching if the soil cannot retain those nutrients effectively. Using more water can also promote leaching, particularly in sandy soils that are already well-draining. Thus, incorporating organic matter offers a sustainable approach to improving soil health and reducing nutrient loss.