Mulch not only conserves soil moisture but also prevents what from competing for nutrients?

The correct answer highlights the role of mulch in inhibiting weed growth. Mulch acts as a barrier on the soil surface, blocking sunlight from reaching weed seeds and seedlings. This suppression of light is crucial because most weeds require sunlight to germinate and grow. By preventing weeds from sprouting, mulch helps ensure that the nutrients in the soil are utilized by the desired plants rather than being competed for by these unwanted plants. Furthermore, the organic matter in mulch can improve soil structure and health over time as it decomposes, further supporting the growth of well-established plants.

In contrast, rocks do not compete for nutrients, as they are inanimate objects. Insects, while they can affect plant health, do not compete for soil nutrients in the same way that weeds do. Fungi, although they play a role in nutrient cycling, interact differently with plants and don’t compete in the same manner as weeds for water and nutrients directly from the soil. Thus, the primary function of mulch in this context is to keep weeds at bay, making it critical for sustainable horticultural practices.