Thank you very much for your inquiry. Grub ex is very effective against Japanese Beetle (JB) grubs as they hatch fro the egg in mid-to late- summer and not very effective at all against the grub any larger than this stage and should not be used. Use dylox instead. Grub-ex should be put down in late June early July before JB eggs hatch and you will then achieve the proclaimed SEASON LONG CONTROL.

Milky spore can work on JB, but it take 3-5 years for the organism to build up a high enough population in the soil and several applications must be made over this time. Once the population is high enough this product works well. You can start treatments this fall with no issues, but you will not see effects for about three years, so keep the dylox and grub-ex handy.

Again, thanks for the question and let me know if you have more.

Respectfully

Trey Rogers
The Yard Doctor

I don't profess to be an expert (far from). However, I can tell you that after our dog passed last summer, moles decided to take over the yard. Only reason I mention that is because we never had a problem in the past and I thought people were nuts that spent money on grubex and the like.

Anyway, in about a few weeks our lawn/roots started to get eaten to shreds (tracks going every which way). I put down Grubex and the moles disappeared. Intend to apply it again this year with hopefully the same results. Happened to come across this thread looking for advice on when to apply and will follow the yarddoctors instructions above.

Regards,
Andrew