Which of the following is not a benefit of mulching in landscape beds?

• A. Conserves soil moisture
• B. Suppresses weeds
• C. Moderates soil temperature
• D. Increases soil salinity

Answer: (D)

Mulching mainly provides three clear benefits: it helps conserve soil moisture by reducing evaporation, suppresses weeds by blocking light needed for germination, and moderates soil temperature by acting as an insulating layer for roots. These effects protect plant roots, improve water efficiency, and reduce competition from weeds.

In contrast, increasing soil salinity is not something mulch provides. Mulch does not add salts to the soil and, in fact, reducing evaporation can help prevent salt concentration at the surface. Only under specific, salt-containing materials or poor irrigation practices would salinity become a concern, but it’s not a intended or typical benefit of mulching.