Dicentra (Greek dís "twice", kéntron "spur"),[1] known collectively as the bleeding-hearts, is a genus containing eight species of herbaceous flowering perennial plants with unique, "heart"-shaped flowers and finely divided foliage. The species are, primarily, native to North America, although several are found in temperate East Asia.
Flowers have two tiny sepals and four petals. The flowers are bisymmetric: the two outer petals are spurred or pouched at the base and curved outwards or backwards at the tip, and the two inner ones with or without a crest at the tip. In Dicentra, all leaves are in a basal rosette, and flowers are on leafless stalks. In other genera with bisymmetric heart-shaped flowers (Lamprocapnos, Dactylicapnos, Ichtyoselmis, Ehrendorferia), leaves grow on stems as well as from the root.[2] Each of the two compound stamens is composed of one median and two lateral half stamens fused together. The stamens and pistil are held between the inner petals.
Native to Northeastern Asia, the Pacific Northwest, as well as parts of the eastern United States, Dicentra almost universally prefer growing in cool, temperate, wet forests with excellent drainage, often growing side-by-side with ferns, Hosta, mosses, and other shade- or dappled-light-loving species, depending on location and region. While Dicentra will bloom in filtered light or shade, if grown in poorly-drained soil and intense lighting, they will not bloom or thrive.[3]
Seeds with elaiosomes are borne in long capsules.
All parts of Dicentra are poisonous if ingested.
The genus Dicentra includes plants whose flowers and leaves grow on stems directly from the roots. Species with branching stems used to be included in the genus, but have now been moved to other genera.
| Image | Scientific name | Common Name | Distribution |
|---|---|---|---|
| Dicentra canadensis (Goldie) Walp. | squirrel-corn | eastern North America | |
| Dicentra cucullaria (L.) Bernh. | Dutchman's-breeches | eastern North America, with a disjunct population in the Columbia Basin | |
| Dicentra eximia (Ker-Gawl.) Torr. | fringed bleeding-heart, turkey-corn | Appalachian Mountains | |
| Dicentra formosa (Haw.) Walp. | western or Pacific bleeding-heart | Pacific Coast of North America | |
| Dicentra nevadensis Eastw. | Sierra bleeding-heart | Sierra Nevada peaks of Tulare and Fresno Counties, endemic to central eastern California | |
| Dicentra pauciflora S. Wats. | short-horn steer's-head | Oregon and California | |
| Dicentra peregrina (Rudolphi) Makino | komakusa | Japan, the Kuril Islands, Sakhalin Island, and northeastern Siberia | |
| Dicentra uniflora Kellogg | long-horn steer's-head | western United States | |
The genera Dactylicapnos, Ichtyoselmis, Ehrendorferia and Lamprocapnos were previously included as subgenera in Dicentra, but have been shown not to belong in this genus (see for example Flora of China)
There are several hybrids and cultivars involving Dicentra eximia, Dicentra formosa, and Dicentra peregrina, including (those marked have gained the Royal Horticultural Society's Award of Garden Merit):-[4]
Hybrids involving Dicentra peregrina are often intolerant of hot, humid climates and sun, like the species itself.