Penstemon, commonly known as Beardtongue, is a popular perennial valued for its vibrant, tubular flowers and long blooming season, often stretching from late spring into autumn. This diverse genus features hundreds of species and hybrid varieties, producing tall flower spikes that attract pollinators like hummingbirds and bees. Removing the faded flowers—a simple maintenance task called deadheading—is one way to manage the plant’s appearance and performance.
Why Deadheading Penstemon Is Optional
Deadheading Penstemon is not necessary for the plant’s survival, but it is a tool gardeners use to influence the plant’s appearance and reproductive cycle. Removing the faded flower spikes primarily conserves the plant’s energy by preventing it from setting seed. This energy can then be redirected toward maintaining healthy foliage and potentially producing new vegetative growth.
For many hybrid varieties, the removal of spent blooms can encourage a second, smaller flush of flowers later in the season, extending the display. This rebloom is a desirable outcome for gardeners who value continuous color in their borders. Furthermore, deadheading maintains a tidy garden appearance by eliminating the brown, wilted flower remnants that can detract from the plant’s overall look.
Conversely, leaving the final set of flowers to mature allows the plant to set seed, which is useful for propagation or encouraging natural reseeding. Native Penstemon species or short-lived varieties are often allowed to produce seed to ensure new plants are available the following year. Allowing seed set on hybrid varieties, however, may result in offspring that do not resemble the parent plant.
How to Deadhead Spent Penstemon Blooms
Deadheading should be performed regularly throughout the blooming season as individual flower spikes fade. The goal is to remove the spent flower stalk, which is the long stem that held the blooms, rather than picking off individual faded flowers. Using clean, sharp tools, such as bypass pruners or scissors, is recommended to make a precise cut and prevent damage.
To execute the cut, follow the spent flower stalk down the stem until you reach the nearest set of healthy leaves or a visible, outward-facing bud. Making the cut just above this node encourages the side shoot to grow and potentially produce a new flowering stem. Taking care not to remove more than one-third of the plant’s overall growth at any one time helps prevent unnecessary stress on the perennial.
Post-Season Pruning and Overwintering Care
Pruning at the end of the season differs from regular deadheading and involves cutting back the entire plant structure for winter preparation or spring rejuvenation. In colder climates, it is recommended to leave the plant’s foliage intact over the winter months. This dead growth provides a layer of natural insulation and protects the crown of the plant from harsh, freezing temperatures.
A hard prune is best carried out in late winter or early spring, just as new growth begins to emerge from the base. Cut the entire plant back, typically to about 4 to 6 inches above the ground, or down to the lowest set of new shoots. This practice prevents the plant from becoming woody and leggy, promoting a fresh, vigorous flush of growth and flowers. Good soil drainage is important for overwintering success, and a light layer of mulch can be applied around the base to protect the roots from extreme cold.