‘Hei Hua Kui’ or King of Black Flowers is a tree peony with dark red cup-shaped blooms surrounding yellow stamens. Tree peonies often need to settle in for one to two years before producing flowers and, once established, will mature to 5 feet in five to eight years. Plant in sun to part shade with the eyes no more than 2 inches below the soil surface and protect from strong winds and afternoon sun. Deer resistant.

Peonies are popular garden plants, known for their stunning flowers, their cold hardiness and the huge variety of their colors, forms, and habits. They are divided into two main groups: herbaceous, which die to the ground in the fall; and tree peonies, which are deciduous plants with woody stems that they retain throughout the winter. A third category—the Itoh or intersectional peonies—display the extravagant blooms of tree peonies on herbaceous stems. All peonies bloom between April and June. Flowers on tree peonies appear one to two weeks before those on herbaceous peonies.