I grew up seeing two, huge bleeding hearts that grew at a friend's house every spring in the town high up in the Idaho Rockies where I was raised. The plants had to have been very old as the house was built prior to 1900. They bloomed profusely and were a source of amazement to me every year. A few years ago, I went back to visit that old house and there they were, blooming like crazy.
However, I've tried them several times in OKC and have not been able to keep them alive through the hot, dry summers no matter what I do to make them feel at home.
Ah well, at least I know they are still growing somewhere!