Red Seal Landscape Horticulturist Practice Exam

What is the primary function of mulch in landscape gardening?

1. To add nutrients to the soil

2. To retain soil moisture, suppress weeds, and regulate soil temperature

3. To attract beneficial insects

4. To provide a decorative finish to garden beds

The correct answer is: To retain soil moisture, suppress weeds, and regulate soil temperature

The primary function of mulch in landscape gardening is to retain soil moisture, suppress weeds, and regulate soil temperature. Mulch acts as a protective layer over the soil that helps to reduce evaporation, which keeps the soil moist for longer periods, benefiting plant health and growth. By covering the soil, mulch also blocks sunlight from reaching weeds, thereby inhibiting their growth and competition with desired plants. Furthermore, mulch can help to maintain a more consistent soil temperature, which is crucial for root development and overall plant vitality. While mulch can certainly contribute to soil health by breaking down and slowly releasing nutrients over time, its main roles extend beyond simply adding nutrients. The aesthetic aspect of mulch provides visual appeal, but that is not its fundamental function in the context of gardening practices. Similarly, attracting beneficial insects is important for the ecosystem, yet this is not a primary role of mulch itself. Thus, the effectiveness of mulch in enhancing moisture retention, weed suppression, and temperature regulation establishes it as an essential component of landscape gardening.