What activates pre-emergent?

Pre-emergent herbicides are designed to prevent the germination of weeds by forming a protective barrier in the soil. Water is the key factor that activates pre-emergent herbicides because it helps to release the active ingredients from the granules or liquid formulations, allowing them to interact with the soil and establish a barrier against weed seeds. When moisture is present, it triggers the chemical processes that enable the herbicide to become effective at controlling weeds before they emerge.

Sunlight, while important for plant growth, does not directly activate pre-emergents. Fertilizer provides nutrients for plants but is not involved in the activation of herbicides. Wind does not play a role in the activation of pre-emergent products, although it may affect their dispersion or application. Therefore, the role of water is crucial in ensuring that the pre-emergent herbicides function as intended, making it the correct choice in this context.