Creeping Phlox (Phlox subulata) is a low-growing perennial treasured for its ability to form a dense, colorful mat across the landscape. This plant is a popular choice for groundcovers, rock gardens, and slopes due to its vigorous, trailing habit and evergreen, needle-like foliage. During spring, the plant becomes completely covered in a profusion of small, starry flowers, creating a spectacular display. Multiplying this plant is straightforward, offering a cost-effective way to expand its presence in the garden.
Essential Timing and Site Preparation
The success of propagation is significantly improved by performing the task when the plant is not under environmental stress, such as intense heat or active blooming. The optimal time for dividing established clumps is in the early spring, just as new growth begins to emerge, or in the late fall, after the flowering period has concluded. Performing propagation during these cooler seasons allows the new divisions or cuttings to focus their energy on establishing a healthy root system before the summer heat arrives. Creeping Phlox thrives best in full sun, though it can tolerate some dappled afternoon shade, and requires well-drained soil. Before beginning, prepare the planting site by loosening the soil and incorporating organic matter, ensuring tools like a spade, garden fork, and pruning shears are clean and sharp.
Method One: Propagating Through Division
Division is the most direct method for increasing stock and is beneficial for rejuvenating older clumps that have become woody. Water the parent plant thoroughly one day prior to the procedure to ensure the root ball is hydrated and less prone to shock. Use a garden fork or spade to carefully dig around the perimeter of the plant, lifting the entire root ball. Gently shake off the excess soil to expose the roots and identify natural points of separation, then separate the clump into smaller sections. Ensure each new piece retains a healthy mass of roots and at least one viable shoot of foliage before replanting immediately into their prepared locations, ensuring the crown is level with the surrounding soil.
Method Two: Taking Stem Cuttings
Propagating Creeping Phlox using stem cuttings is an effective method when multiplying a specific variety or when division is not practical. The best material for this technique is a healthy, non-flowering stem from the new season’s growth. Use sharp, sterile shears to take cuttings that are approximately four to six inches long, making the cut just below a leaf node. Prepare each cutting by removing the foliage from the lower one-third of the stem to expose the nodes where new roots will form; dipping the cut end into rooting hormone can accelerate development. Insert the prepared cuttings into a sterile, well-draining rooting medium, such as peat moss, coarse sand, or perlite, ensuring the bare nodes are covered, and place them in a sheltered environment away from direct sunlight.
Establishing and Caring for New Plants
Immediate and consistent care is necessary to ensure successful establishment. New divisions should be thoroughly watered immediately after planting to help the soil settle around the roots and eliminate air pockets. For the first few weeks, the soil must be kept moderately moist until the plants show clear signs of new growth. Stem cuttings require a controlled environment; place the pots in a warm spot that receives bright, indirect light. To maintain high humidity, cover the container with a clear plastic dome, removing it daily for air circulation, and once established, gradually acclimate the rooted cuttings to outdoor conditions before transplanting.