Japanese woody peony. In the last year I have already mentioned, but now I repeat it because it is important that the Japanese sports are more frost-hardy than the Chinese one. This one is for example Z4 (that is, down to -34 ºC).
It has just opened this afternoon. Have a look at its pictures from the last year, too! And if you are interested, check its page in the fantastic Paeonia database of Carsten Burkhardt.
I have purchased our peonies from the German nursery Staudengärtnerei Gräfin von Zeppelin. Now they offer 180 sports, more than 50 of them woody ones. Watch their page even if you do not want to buy, their photos are beautiful and true to life. And if you need good quality plants, you are encouraged to buy of them.