- A low maintenance Peony, if there ever was one. Has to be my favourite. Healthy green foliage. Similar to a tree Peony. Resistant to common Peony problems. The foliage looks great from Spring through Fall and doesn't require staking. Produces very lare, strong, double-yellow flowers. They measure 6-8" across. Bartzella is a itoh type Peony which is a cross between a Garden Peony and a Woody Peony. While initially more expensive than a traditionally Garden Peony, it will own its keep in your garden. Height & Spread 30".