Phlox subulata, or creeping phlox, is an evergreen ground cover with needle-like foliage and vivid flowers in spring. According to the USDA, the plant is native to parts of North America. Many hybrids have been cultivated and flowers come in colors ranging from blue to pink to magenta to white. Hardy in USDA Plant Hardiness Zones 3 to 9, creeping phlox is easy to grow once its basic requirements are met. If you want more phlox, divide the clump after flowering and replant.
Where to Plant
A site with six hours or more of sun is ideal. Too much shade will cause the plant not to flower and the foliage will become sparse. Ohio State University suggests a well-drained soil that holds moisture but adds that phlox is "adaptable" to many soil situations, including dry and rocky. Consider planting phlox on slopes or allowing the plant to drape over walls or even grow in containers.
How to Plant
Phlox subulata is widely available in pots or are field-grown and shipped to nurseries in brick-shaped containers. Tap the plant out of the pot or container and loosen any tight roots. Dig the hole twice as wide and deep. Fill the hole with organic planting mix, place the phlox in the hole and backfill, adjusting the plant so that the soil level is the same as in the pot. Water in well and again every few days for the first week.
Phlox subulata blooms for approximately two weeks in late April and early May. After flowering, cut the plant back about one-third to help regain foliage density, according to Ohio State University. An unpruned creeping phlox will become more woody as it ages. Foliage may yellow after flowering, but does become green again towards fall. Fertilize annually with an all-purpose fertilizer for flowering plants.
What to Expect
Some varieties of phlox spread slowly and others grow at a steady rate, according to "Fine Gardening Magazine." Although creeping phlox is extremely hardy, Ohio State University recommends a winter mulch of evergreen boughs. Phlox is low-maintenance but sometimes gets spider mites and powdery mildew. Foliar nematodes may occur during humid, rainy weather.
What Experts say
The University of Georgia Trial Gardens in Athens, Georgia grew the varieties Phlox subulata 'Emerald Pink',' Scarlet Flame,' and 'Drummond's Pink,' and gave these plants a 5 rating, with 5 being the best. Phlox subulata 'Oakington Blue' received a 4.5.