Botanical Name: Phlox subulata ‘Emerald Blue’

Common Name: Creeping Phlox, Moss Phlox

Hardiness Zone: Perennial in Most Climates (USDA Zones 3–9)

Size: 4–6" Tall × 18–24" Spread

Growth Habit: Low-Growing, Mat-Forming, Spreading Habit

Sunlight: Full Sun (Best Flowering); Tolerates Light Shade

Soil: Prefers Well-Drained Soil; Tolerates Sandy or Rocky Soils

Water Needs: Low to Moderate; Drought Tolerant Once Established

Bloom Season: Early to Mid-Spring

Fertilizer: Minimal; Light Feeding in Early Spring if Needed

Features: Soft Blue-Lavender Flowers, Evergreen Needle-Like Foliage, Excellent Erosion Control, Deer Resistant

Uses: Ideal for Ground Cover, Slopes, Rock Gardens, Edging, and Over Walls

Patent: ❌ Not Patented

Propagation: ✔ Propagation Allowed

More About Creeping Phlox ‘Emerald Blue’

Creeping Phlox ‘Emerald Blue’ is a time-tested spring favorite, valued for its dense carpet of soft blue-lavender flowers that completely cover the plant in early spring. During peak bloom, the foliage is nearly hidden beneath a blanket of color, creating one of the most dramatic seasonal ground-cover displays available.

After flowering, the plant transitions into a tidy mat of evergreen, needle-like foliage that provides year-round texture and coverage. Its ability to thrive in poor, rocky, or sloped soils makes it especially useful in challenging landscape areas.

Why We Like It (Our Trials)

In our trials, ‘Emerald Blue’ has been exceptionally reliable, especially in full sun and well-drained soils. It establishes quickly, spreads steadily without becoming invasive, and requires very little maintenance once established.

We especially appreciate its versatility. It works beautifully cascading over walls, filling in slopes for erosion control, or lining walkways and borders where early-spring color is needed. Deer typically leave it alone, and it pairs effortlessly with spring bulbs and other early perennials.

Creeping Phlox ‘Emerald Blue’ vs. Other Creeping Phlox

Emerald Blue delivers a cooler, more tranquil color experience than Emerald Pink, favoring soft blue tones over deep, dramatic pinks. Compared to Amazing Grace, Emerald Blue provides more color presence while maintaining a refined, balanced look. Emerald Blue is the strongest choice when a calming, cohesive Spring palette is desired.

Compared to Spring® Scarlet, Emerald Blue is intentionally subdued, offering balance rather than intensity. And next to Candy Stripe, Emerald Blue provides a uniform, grounded appearance instead of visual pattern and contrast. For gardeners looking to create peaceful, natural-looking plantings with consistent color, Emerald Blue is the clear choice.