What is the primary action required after applying an insecticide for white grubs?

Watering in insecticide is crucial after applying it for controlling white grubs because these pests typically reside in the soil beneath the turf. The application forms a barrier on the surface, but for it to be effective, the insecticide needs to penetrate into the soil where the grubs are feeding. Watering helps move the insecticide down to the root zone, ensuring that it reaches the target pests effectively.

This practice enhances the efficacy of the treatment, allowing the insecticide to interact with the grubs as they feed on the roots of the grass. It's important to follow the manufacturer’s recommendations regarding the amount and time frame for watering after application to optimize pest control and minimize potential runoff.