The Black Lace Elderberry (Sambucus nigra cultivar) is a popular ornamental shrub valued for its deeply dissected, purple-black foliage and contrasting pale pink flowers. This deciduous shrub provides an architectural element to the garden, but its fast-growing nature requires regular management. Pruning is a necessary annual practice, ensuring the plant’s long-term health and preserving its distinctive aesthetic qualities. Proper techniques manage its size, promote vibrant color, and renew the woody structure.
Characteristics of Black Lace Elderberry
The ‘Black Lace’ elderberry naturally exhibits a rapid, upright, and somewhat sprawling growth habit, quickly achieving a mature height and spread of between six and eight feet. If left unmanaged, the shrub can become dense, congested, and “leggy” at the base due to older, woody canes becoming less vigorous over time.
Pruning encourages the production of new, young canes, which display the most intense purple-black foliage color. New growth is consistently more vibrant than older leaves, which can fade to a greenish-purple, especially in warmer climates or partial shade. Although the shrub produces flowers and berries on old wood, many gardeners prioritize the foliage, making size management and color promotion the primary goals of the annual pruning regimen.
Ideal Timing for Pruning
The optimal time to prune the Black Lace Elderberry is during its dormant period, specifically in late winter or very early spring, generally from February through early April. Pruning while the plant is dormant, before new leaf buds begin to swell, minimizes stress on the system. This timing also allows the gardener to clearly see the shrub’s structure without foliage, making it easier to identify and remove old or poorly placed canes.
Pruning during dormancy is beneficial because large cuts heal quickly once the plant enters its growth phase, reducing the chance of disease or pests entering open wounds. Elderberries are known to “bleed” or weep sap if cut after active growth has started, so performing the work before this period avoids that issue. Before making any cuts, all pruning tools, including hand pruners and loppers, should be sharpened and sanitized with rubbing alcohol or bleach to prevent the transmission of pathogens.
Step-by-Step Pruning Techniques
Pruning the Black Lace Elderberry involves two distinct approaches: annual maintenance for shape and size control, and periodic hard cuts for rejuvenation. The most common form of annual pruning focuses on thinning out the oldest, weakest, and most congested canes to maintain an open structure. This involves removing approximately one-third of the oldest canes, cutting them off cleanly at the base of the plant near the ground line.
When thinning a cane, the cut should be made flush with the ground or the parent stem, which encourages vigorous new shoots to emerge from the base. For shaping cuts on the remaining younger canes, always trim back to a point just above an outward-facing bud or a healthy side branch. This redirects the plant’s growth outward, preventing the center from becoming too dense and improving air circulation.
An alternative, more aggressive technique is hard pruning, also known as coppicing or stooling, which is performed every three to five years. This method involves cutting the entire shrub back severely, taking all canes down to within six to twelve inches of the ground. This drastic cut sacrifices all flowers and potential berries for the current season, as the plant blooms on the previous year’s wood.
The trade-off for sacrificing blooms is the assurance of the most vigorous new growth and the darkest, most intense foliage color possible. Immediately following a hard pruning, the plant should be provided with a balanced, slow-release granular fertilizer in the early spring. This extra nutrition supports the flush of new growth that will emerge from the remaining stubs, allowing the shrub to quickly regain its size and density by the end of the season.