This is called Lychnis "Angel Blush," and there is a very slight pink blush to the new blossom, but it turns bright white, almost a repeat of a bright white impatiens at the front of the border. This is a new plant for me--I bought it when my friend The Garden Curmudgeon took me to Sandy's Plants in Richmond (by the way, thanks, Tina, for showing me how to do links properly!).
A digression within a digression: Sandy's is a must-see. She has acres of perennials, so we have to drive around in golf carts to get our plants. I made the mistake of riding with the Curmudgeon the first time, who quickly filled up the back of the cart with his stuff (ok, he's a landscape designer and he was shopping for a client, but still)--one really needs one's own cart at Sandy's. One also really needs a shopping list: first, because you need to find the plants you want on the map so that you know where to drive the golf cart; and second, because if you don't have a list, you'll do what I did, and buy on impulse, which is very dangerous when you're surrounded by acres of plants and one of those acres (ok, about one of those acres, I didn't actually measure) is dedicated to native plants. Still, the impulses worked--one was the rose campion, whose gray foliage looks stunning next to near-black heuchera "Obsidian" (also from Sandy's) and bright green deutzia gracilis "nikko" (from Lowe's years ago)--the sun-loving plants surrounding it shade the heuchera and sweet woodruff beneath it very nicely.
I realize, by the way, that none of the plants I just mentioned are natives--but on that same trip, I did get some beautiful native columbine, some Virgina bluebells, and something they couldn't quite identify that's some kind of foam-flower (they had decided it was too prolific and so they weren't going to sell it--I apparently found a left-over so they gave it to me--it may end up in one of these "too-much-of-a-good-thing" posts, but for now, it's just a good thing).
But even if Richmond is a bit of a hike for you, Sandy's website is a wonderful source of information--she has a whole section devoted to one of my favorite topics, deer-resistant plants.
Happy Fourth of July!