Creeping phlox (Phlox subulata) is a low-growing perennial admired for its dense, mat-forming habit and abundant spring bloom. Unlike taller plants where deadheading involves pinching off individual spent flowers, the sheer volume of small blooms makes this method impractical. Instead, a specialized approach called “shearing” is used. This technique efficiently removes all faded flowers and a portion of the foliage, promoting a denser, healthier groundcover after the flowering period.
The Timing and Purpose of Shearing
The optimal time to shear creeping phlox is immediately following the conclusion of its main spring bloom, typically from late May into early June. Performing this cut promptly stops the plant from expending energy on setting seed, redirecting resources into root development and new vegetative growth. This strategic pruning prevents the plant from becoming “leggy,” where stems become long and sparse, compromising the dense mat appearance. Trimming encourages the development of fresh, compact foliage that maintains the plant’s tidy appearance throughout the summer. This energy reallocation can also prompt a small, secondary flush of blooms later in the season.
Step-by-Step Shearing Technique
The physical act of shearing can be accomplished using sharp, clean garden shears or, for larger patches, electric hedge trimmers. The technique involves giving the entire mat a uniform “haircut” across the surface. Aim to cut back the plant by approximately one-third to one-half of the current year’s green growth, removing the spent flower heads and the top layer of foliage.
It is important to make the cut above a set of healthy, green leaves, as this is where the new growth will emerge. Avoid cutting deeply into the older, woody stems near the base of the plant, since these parts do not readily produce new foliage and can leave bare patches. The goal is a light, uniform trim that shapes the mat, removes the dead material, and encourages lateral branching for a thicker groundcover. This annual haircut helps prevent the center of the plant from dying out, which often happens when the mat becomes too dense.
Essential Post-Shearing Maintenance
After shearing, the plant requires immediate attention to support its recovery and new growth. Begin with a thorough, deep watering, especially if the soil is dry, to help settle the plant and hydrate the roots. Prompt watering is important because removing foliage reduces the plant’s ability to retain moisture.
Following the initial watering, a light application of a balanced, slow-release fertilizer is beneficial to fuel the new development. A slow-release granular product or compost provides the necessary nutrients without causing excessive, weak growth. Monitor the plant closely in the weeks following the cut for any signs of distress or pests, ensuring a swift and healthy recovery.