Which of the following is a benefit of using mulch in landscaping?

Using mulch in landscaping offers numerous benefits, one of which is the significant reduction in the need for weeding. When a layer of mulch is applied to the soil surface, it effectively suppresses weed growth by blocking sunlight from reaching weed seeds. This creates a less favorable environment for weed germination and growth, allowing desirable plants to thrive with less competition. Additionally, the barrier mulch creates helps retain moisture in the soil, further reducing the need for labor-intensive weeding efforts.

In contrast, the other options highlight outcomes that are either negative or not true. For example, while mulch can help retain soil moisture, it does not eliminate the need for irrigation, especially in dry conditions. Additionally, far from attracting pests, mulch can actually help deter some pests and provide a habitat for beneficial organisms. Lastly, mulch typically does not increase soil salinity; rather, it aids in maintaining a healthy soil environment.