Landscaping License Practice Test

What is the purpose of adding compost to soil?

1. Increase soil pH

2. Enhance soil fertility and structure

3. Reduce water retention

4. Prevent erosion

The correct answer is: Enhance soil fertility and structure

Adding compost to soil serves multiple beneficial purposes, and enhancing soil fertility and structure is one of the primary reasons. Compost is rich in organic matter, which is essential for improving the nutrient content in the soil. When compost is mixed into the soil, it releases essential nutrients slowly over time, providing a steady supply that promotes healthy plant growth. Additionally, compost improves soil structure by increasing its ability to hold moisture while allowing for proper drainage and aeration. This combination results in a well-aerated, loamy soil that supports root development and enhances microbial activity. The presence of beneficial microorganisms in compost helps in further breaking down organic material, thus enriching the soil. In contrast, options such as increasing soil pH may not directly relate to compost use because compost can either neutralize soil pH or help maintain it without necessarily causing any significant increase. Similarly, compost generally does not reduce water retention; rather, it improves the soil's ability to retain moisture. Preventing erosion is indirectly related, as better soil structure can reduce erosion risk, but the core purpose of compost addition is primarily about enhancing fertility and overall soil health.