Creeping Phloxnative cultivar
Phlox subulata 'Emerald Blue' · Polemoniaceae
Field guide
'Emerald Blue' is a mat-forming cultivar of eastern North American moss phlox, growing 4–6 in. tall and spreading 12–24 in. into a moss-like carpet of evergreen needle-like foliage smothered in lavender-blue star-shaped flowers in early-mid spring. It demands full sun and sharp drainage, tolerating sandy or rocky soils, drought and heat better than most phlox. Older stems become woody and bare unless sheared after flowering. Excellent on slopes, in rock gardens and as edging.
Gardener's notes
Plant it where it will bake in full sun with fast drainage—it sulks and gets mildew in rich, damp soil. The moment your spring flush fades, shear the whole mat back by half for tighter, fresher growth and fewer woody bare patches.
Ecology
- Pollinators: butterflies, bees, bee-flies, occasional hummingbird
- Larval host for: possible minor sphinx/Schinia moth host (uncertain)
Care this season
- Pruning: shear by half after bloom for dense regrowth and fewer woody bare patches
- Deadheading: shear-for-rebloom
- Pests: spider mites in hot dry sites, rabbits nibble
Meaning
Phlox = Greek for flame; subulata = awl-shaped (the leaves). Moss pink heralds spring across Appalachian ledges, woven into cottage-garden tradition. Soft cushion texture, faint sweet scent, sheets of color—the earliest, toughest groundcover carpet.
Sources
- Phlox subulata 'Emerald Blue' — NC State Extension
- Phlox subulata — Missouri Botanical Garden
Notes: Named clone—wildlife value tracks the species but is genetically uniform. Larval-host status low/uncertain, flagged false. Some sources list the cultivar as 'Blue Emerald'.