Culture
Easily grown in average, medium moisture, well-drained soils in part shade. Prefers rich, fertile, humusy, consistently moist soils. Soils must not be allowed to dry out during summer. Intolerant of wet soils in winter. Promptly remove spent flowering stems to promote additional bloom.
This is a sterile hybrid that must be propagated vegetatively.
Noteworthy Characteristics
Dicentra is a genus of 20 or more species of annual and perennial herbaceous flowering plants which are native to moist woodland areas in Asia and North America. Plants feature pendant, two-spurred, heart-shaped flowers atop mounds of deeply dissected leaves.
A number of cultivars have been produced in recent years which are hybrid crosses between D. peregrine (native to alpine areas of China and eastern Siberia) and D. eximea (native to woodland areas of eastern North America) in which the goal was to produce a dicentra with a compact and robust habit, long flowering period, blue-gray foliage and quality flower colors.
Genus name comes from the Greek words dis meaning twice and kentron meaning a spur for the two-spurred flowers.
Flowers in the genus Dicentra are commonly called bleeding heart because protruding inner petals, more obvious in some species than others, purportedly appear to form a drop of blood at the bottom of each heart-shaped flower.
‘King of Hearts’ is a compact bleeding heart hybrid cultivar resulting from a cross of the Japanese species D. peregrina with two American species D. formosa subsp. oregana and D. eximia. It typically produces a foliage mound to 6-8” tall and 14” wide of deeply-cut, fern-like, bluish-green leaves that persists throughout the growing season. Nodding, heart-shaped, rich carmine-rose flowers are carried above the foliage to 10-15” tall on long, leafless, erect to slightly leaning stems. In St. Louis, primary bloom is in May and June, with flowering slowing down considerably or stopping in the heat of the summer, but with a possible rebloom occurring when the weather cools in late summer to early fall. Flowering may continue throughout the summer in cool northern climates. Given adequate moisture, the foliage remains attractive in summer, and may produce an attractive ground cover effect. ‘King of Hearts’ is sometimes sold as a cultivar of D. formosa notwithstanding its hybrid parentage.
Problems
No serious insect or disease problems. Some susceptibility to aphid infestations. Powdery mildew, downy mildew, verticillium wilt, fusarium wilt and rust may occur. Good soil drainage is essential for plant survival. Slugs and snails may attack new growth.
Uses
Mass, group or specimen in woodland gardens or shaded areas borders and rock gardens. Foliage can be quite attractive when flowers are not in bloom.