Answer: Timing is really important when using a grub control product. Using it now won't have any effect on the grubs because they are not close enough to the surface to come in contact with the product. They are not feeding on the grass roots at this time of year, either, so whatever damage they might do, they have already done. Wait until the proper time (usually July or August, depending on weather) to use your grub control product and it will be much more efficient. Best wishes with your landscape.
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