I started using it at the beginning of last year. But then, I also started using alfalfa pellets.
I'm not able to tell if either made any difference because of this year's abundant rainfall. We seldom have rain like we did this past spring.
I have had better rebloom than ever this season, but was it because of the abundant rain or the Milorganite and alfalfa? Would I have gotten the same results if I had to hand-water, as usual? I don't know.