The Bleeding Heart, botanically known as Lamprocapnos spectabilis, is a beloved perennial celebrated for its unique, heart-shaped flowers that dangle in rows from arching stems. This classic garden plant is one of the earliest to provide vibrant color in the spring garden, known for its distinctive pink and white blooms. Its popularity stems from its reliable display and graceful form, often making it a centerpiece in shaded garden beds.
The Standard Bleeding Heart Bloom Cycle
The flowering period for the common or “old-fashioned” Bleeding Heart (L. spectabilis) typically lasts between four to six weeks. Its display begins in mid-to-late spring, often coinciding with the bloom of late daffodils and tulips, and extends into the early summer months.
The Fringed Bleeding Heart (Dicentra eximia) and its hybrids, such as ‘Luxuriant’, exhibit a notably different bloom cycle. These varieties are often more compact and can flower almost continuously from spring through summer and even into the fall.
Environmental Triggers That End Flowering
The primary factor dictating the end of the Bleeding Heart’s bloom is temperature, as this plant is genetically programmed for cool-weather performance. The plant thrives when daytime temperatures remain within an optimal range of approximately 55°F to 75°F (13°C to 24°C). When temperatures consistently climb above 80°F (27°C), the plant perceives this heat as a signal to enter its summer dormancy phase.
This heat stress causes the plant to abruptly stop flowering and initiates the process of senescence, where the energy stored in the foliage is rapidly transferred back to the fleshy roots. Excessive direct sunlight accelerates this heat-induced dormancy. Inadequate soil moisture compounds the problem, as dry conditions raise the temperature around the roots, triggering the plant to shut down its above-ground growth faster.
Strategies for Extending the Display
The most effective way to prolong the spring display is by controlling the plant’s microclimate, mitigating the effects of heat and sun. Planting the perennial in a location that receives partial to full shade is important, specifically ensuring it is shielded from the hot, direct sun of the midday and afternoon. The intense light causes the delicate foliage to scorch and hastens the signal for summer dormancy.
Maintaining consistent soil moisture throughout the spring blooming period helps keep the root zone cool, which delays the onset of the heat-triggered dormancy. Deep, thorough watering is preferable to shallow sprinkling, as it encourages deeper root growth and better temperature regulation in the soil. Applying a layer of organic mulch, such as shredded bark or compost, helps insulate the soil, conserve moisture, and suppress temperature fluctuations.
For the repeat-blooming varieties, the careful removal of spent flowers, known as deadheading, encourages the production of new buds. This action prevents the plant from diverting energy into seed development. While deadheading is less effective for the common L. spectabilis, it is a worthwhile practice for the fringed and hybrid varieties to maximize their extended season.
Managing the Plant After Bloom
Once the Bleeding Heart has completed its flowering cycle, typically during the warmer months of early summer, the foliage will naturally begin to yellow and wither. This process is the plant entering its normal summer dormancy, and it is a sign of a healthy perennial preparing for its resting phase. The plant is storing energy in its underground roots for the following spring’s emergence.
Gardeners should resist the urge to immediately remove the fading foliage. Cutting it back too soon prevents the plant from fully reabsorbing all the stored nutrients back into the root system. The yellowed stems and leaves should only be cut back to about one or two inches above the ground once they have completely turned yellow and withered.
The subsequent void left by the dormant Bleeding Heart can be managed by planting suitable companions that thrive in similar shady conditions and emerge later in the season. Shade-loving perennials such as Hostas, Astilbes, and ferns are excellent choices, as their summer growth will fill the space left by the Bleeding Heart’s disappearance, maintaining continuous visual interest.