Late August was probably best time to apply Milky Spore to manage this years Japanese Beetle Grubs. Last year – product was applied in late September in our yard if my memory is correct. We are running late this year do to finances. Don’t have extra money right now to make purchase. I doubt Milky Spore would be given full credit by others. But I feel we had less Japanese Beetle damage than year before. Our landlord did have a local lawn company come and apply insecticide to the trees this summer. That poison was minimally effect if at all.