no doubt, unless its a torrential downpour i prefer to apply in the rain or under running sprinklers. that way i know for sure its watered in properly. any ferts, fungicides, most insecticides, any pre-m's, and some post-m's are best watered in. i do a pretty good job of educating my customers about what i do and why, so if its by chance me you saw.... go ahead and call them. not only will they not fire me, but they will tell their friends that you dont have a clue what yer doing. hahahahahahaha