Deer ate all my plants except for 3 thorny roses. They even tried to strip them, but finally gave up.
Are there any flowers that are deer proof. (not deer resistant, but proof tested!)
There are no guarantees. When deer are hungry enough, they'll eat just about any plant they can reach. You may have to adjust your expectations a bit.
So far they don't eat my Lychnis coronaria, marigolds, Corydalis lutea, hellebores, Caryopteris, Amsonia, Eupatorium 'Chocolate', Epimedium, Irises, Weigelia, Salvia coccinea and S. greggii..... I assume you only mean flowering plants and shrubs. I don't do many annuals so can't comment much on them. The deer left my self-seeded larkspurs alone. They really are hoofed locusts!
The deer have not yet eaten snapdragons, perovskia, four o'clocks, chrysanthemums, particularly leucothoe which is a native, zinnias, various floweriing herbs. For the first time they gobbled up the lilies of the valley! Their desires and preferences definitely change from year to year.
About the only perennials/shrubs they haven't eaten from my garden are monkshood, foxglove, rose of sharon, hellebores and carolina all spice bush. And of course the poison ivy.
Some years they have beem more all consuming than others.