Ants are drawn to sugar whether on your peony buds or your bird feeders. They do no harm to the peonies but should be prevented from reaching your humming bird feeders. Al

There really isn't any way to keep ants off your peonies. Just my opinion, but I think you're wasting your gardening time squishing them! I have so many other more dastardly things to squish, such as caterpillars, LOL! Ants won't do any harm, and if you want to pick the flowers to bring them in, you can just give them a vigorous shake and the ants will fall off.