Is milky spore (St Gabriel) safe and useful to get rid of lawn grubs?
Wayne County Michigan
So far research does not show milky spore products to be effective in Michigan. This may be because it doesn’t survive our winters. Healthy turf with deep roots can survive feeding by grubs. To get healthy turf follow best practices such as mowing no shorter than 3 inches, irrigation and rainfall that totals 1 inch water per week, and fertilize according to a soil test.
Here are some milky spore references-