Hello Vera,

For about the next month, the best Insecticides to apply for grub reduction are imidacloprid, thiamethoxam, clothianidin or chlorantraniloprole.  During September and later, these insecticides will have no effect on grubs,  In the fall and next spring, you need to apply a different control.  This information along with a method to determine if you have a significant enough population of grubs to apply insecticides is contained in the following article:

https://www.canr.msu.edu/news/how_to_choose_and_when_to_apply_grub_control_products_for_your_lawn