I wish it was mine!

Once again I was lurking about looking over the fences at my neighbours' gardens, admiring their plants. I have no idea what this is but it's pretty.
Years ago when I was am embarrassed teenager my aunt used to take a poly bag and a pair of scissors when we went out for a walk just in case she spotted a plant in someone's garden from which she would surreptiously take a cutting. I haven't got to that stage yet!