What type of mulch retains moisture, keeps roots cooler in summer, and prevents growth?

Organic mulch is the correct answer because it is made from natural materials such as leaves, grass clippings, straw, and composted bark. When applied to the soil surface, organic mulch effectively retains moisture by minimizing evaporation. This moisture retention is crucial for maintaining healthy plant growth, especially during hot summer months when water demand increases.

Additionally, organic mulch contributes to regulating soil temperature. By covering the soil, it creates a barrier that helps keep the roots cooler in summer, which is essential for preventing heat stress in plants. The decomposition of organic mulch also enriches the soil over time, promoting nutrient availability for plant uptake.

Moreover, organic mulch inhibits the growth of weeds by blocking sunlight, which prevents weed seeds from germinating and establishing themselves. This results in less competition for nutrients and water between desirable plants and unwanted weeds, creating a healthier garden environment.

In contrast, inorganic mulch, while effective at moisture retention, lacks the added benefits of improving soil quality. Plastic mulch can also retain moisture and prevent weed growth, but may not regulate soil temperature as effectively and can create other issues, such as preventing water infiltration. Wood chips, while beneficial in many ways, can also allow for some weed growth unless applied in a thick layer.