Does irrigation after applying pre-emergent herbicides provide any benefits?

Irrigation after applying pre-emergent herbicides is beneficial because it helps activate the herbicide and integrate it into the soil. Pre-emergent herbicides work by forming a barrier in the soil that prevents weed seeds from germinating. To be effective, these products often need to be activated by moisture, which is where irrigation plays a crucial role. When irrigation occurs after application, it ensures that the herbicide begins to break down into the soil and forms that necessary barrier.

For this reason, it is important to apply the herbicide and then irrigate adequately, usually within a specific timeframe that allows the herbicide to start working effectively. This activation process helps ensure that the product will provide the desired weed control for the subsequent growing season.