Wheedwacker - yes, it works, but only part time it seems. not nearly as effective as its made out to be. at least not for us. I used to use Cory's because it would kill on contact. which was great! hard to find now around here though.
Cinta - perhaps I applied my coffee grounds wrong... how do you do it? a light sprinkle or more heavy? im assuming you surround the entire plant? how soon do you reapply it after it rains or while its raining?