What does mulch provide as a mechanical weed control strategy?

Mulch serves as an effective mechanical weed control strategy primarily by acting as a barrier against weeds. When applied to the surface of the soil, mulch creates a physical barrier that inhibits light penetration, which is essential for weed seeds to germinate and grow. The presence of mulch reduces the available sunlight for unwanted plants, thus preventing their establishment and growth.

Additionally, mulch can suppress the growth of existing weeds by restricting their access to nutrients and water, as it covers the soil surface and competes for these resources. The layer of mulch also helps to maintain a stable temperature for the soil, which benefits desired plants while further inhibiting weed development. In summary, using mulch is a practical approach to controlling weeds mechanically by blocking light and limiting the resources that weeds need to survive.