Paeonia

Two years ago I had a quite similar entry. I can't remember whether it was the same plant or another. Anyway, I know of two blossoms currently in our garden, and several buds in multiple sizes.
For me these flowers are a sign that summer is coming. In German they are called Pfingstrosen, what would translate to Pentecost Roses. And Pentecost is (one of) the last Christian holidays before summer.