Despite the political overtones now attached to their name, bleeding hearts (Dicentra spp.) have charms to captivate even the most conservative gardeners. In spring, heart-shaped blossoms dangle from their branches like charms on a vintage "going steady" bracelet. By midsummer, fernleaf bleeding heart's (Dicentra spectabilis, Lamprocapnos spectabilis) clumps of lacy, soft-green foliage often fade like a forgotten dream. Fringed bleeding hearts (Dicentra eximia) continue through summer as mounds of lacy, silvery foliage, and may rebloom in fall. Perennial in U.S. Department of Agriculture plant hardiness zones 2 through 9, depending on variety, bleeding hearts benefit from an occasional trim to prolong their flowers, tidy them and prevent their unwanted spread.
Deadheading Bleeding Hearts
Although it may sound a bit like a trip to the guillotine, deadheading a bleeding heart's old flowers actually encourages it to produce new ones. The plants flower only long enough to produce seed; if the first round of blooms gets the job done, there won't be another. Deadheading also stops fringed bleeding heart from scattering seeds to grow where they aren't wanted.
Put on a long-sleeved shirt and waterproof gloves before pruning the plant so its sap won't irritate your skin.
Snip a stem of spend flowers off at the main foliage clump.
Place the cut stem in a sealable plastic bag for later disposal.
Disinfect pruner blades with a clean towel or rag moistened in rubbing alcohol.
Repeat the process for all the fading stems, and seal the trash bag and place it in the trash.
Fernleaf Bleeding Hearts
In hot summer climates, fern-leaf bleeding hearts typically go dormant in midsummer. Their foliage gradually turns yellow and dies back to the ground. Because the yellow leaves have stopped photosynthesizing food for the plant, cut them back if you don't like the way they look. They'll return in the spring.
Using the same protective clothing and bypass pruners you would for deadheading, cut the foliage stems back to 1 or 2 inches from the soil line.
Fringed Bleeding Hearts
Fringe bleeding hearts keep their foliage until the first killing fall frost. When that occurs, cut the stems back to 1 or 2 inches from the soil.