From DoMyOwn
https://www.domyown.com/merit-05-insecticide-granules-p-301.html
Merit Granule is actually manufactured by Bayer and is always our top recommendation for grub control. For best results, make application prior to egg hatch. To find out when grub egg hatch normally occurs in your area you should contact your local cooperative extension office.
A reminder has been put into the calendar in May to be ready to spread treatment in June.
The BugDoc answers questions on season-long grub control
See a video here by Doc about the preventative and killer chemicals from Bayer. Also see his page here.
Preventative – Bayer Advance Grub Control & Turf Revitalizer. Apply in late spring. He said June and lives in Georgia.
Killer – Bayer Advance Grub Killer Plus