Dylox is used as a curative for grubs. It is only active for 48 hours. The active ingredient is Trichlorfon. Milky Spore will last in the soil for up to 10 years. This is a natural product made out of grub spores.
We would recommend using Milky Spore if you are wanting long term control. This needs to be applied 6 times a year for two years.
Dylox 6.2 Granules should not harm earthworms as they feed differently than the other targeted insects.
Dylox 6.2 Granules are only active and kill for 48 hours, so grubs also need to be active in the area at the time of application. It starts working immediately after irrigation or rainfall. For best results, the product should be watered in for at least 1 to 1/5 hours after application to ensure the product make it through the thatch layer to where the grubs are feedings. Mature grubs usually require at least 2 applications, 3 to 4 days apart.
Dylox 6.2 Granules - 30lb. bag would not penetrate through mulch and would need to be heavily watered in to get down to the soil below it or you can rake the mulch back before applying Dylox and watering in, then move it back.
Dylox cannot be applied within 20 feet of a well or cistern, per Bayer.