Badcat,
I have more than my share of critters, and I do think the Milorganite helps to deter them some, but this is all about just getting bigger and better blooms and trying to assure rebloom later in the season. I started using the Milorganite because of a video by Dan Hansen, he said it was one of the best things to green up daylilies early. I guess that is also where I got the lawn fertilizer recommendation.