How to Grow Phlox subulata — Moss Phlox

Phlox Subulata

Moss phlox or creeping phlox–botanical name Phlox subulata–is a dense evergreen perennial that forms cushions of bright green leaves. Starry purple or red, sometimes violet-purple, lilac, pink, or white flowers appear in groups in late spring and early summer.

Moss Phlox–Phlox subulata–can be used as a small-scale ground cover or foreground plant in beds and borders. Moss phlox flowers for a month starting in late spring. The plant is smothered in small blossoms, lavender-blue, white, and shades of pink and violet.

Get to Know Moss Phlox

  • Plant type: Evergreen perennial
  • Growing Zones and range: 2-9
  • Hardiness: Hardy to -30ºF (-34ºC); moss phlox does not like heat or drought.
  • Height and width: 2 to 6 inches (5-15cm) tall; to 20 inches (50cm) wide
  • Habit: Lax, forming cushions or mats
  • Foliage: Hairy, linear to elliptic, bright green leaves to 3/4 inch long
  • Flowers: Star-shaped petal lobes; white, pink, or lavender blooms
  • Bloom time: Spring blooms followed by lush green foliage
  • Uses: Matlike groundcover, hillsides
  • Common name: Moss Phlox, creeping phlox
  • Botanical name: Phlox subulata
  • Family: Polemoniaceae
  • Origin: North America

Where to Plant Moss Phlox

  • Plant moss phlox in full sun.
  • Grow moss phlox in average or poor, rocky soil that is dry. Moss phlox prefers alkaline soil.

Moss Phlox Uses and Companions

  • Use Phlox subulata as a groundcover or ending in informal beds and borders.
  • Plant Phlox subulata in a rock garden.
  • Good companions for moss phlox include Aster, Chrysanthemum, Monarda, Physostegia viginiana, Platycodon grandiflorus.
Creeping phlox, Phlox subulata
Creeping phlox, Phlox subulata

When to Plant Moss Phlox

  • Set established moss phlox in the garden in spring. Divide plants in the fall.

Planting and Spacing Moss Phlox

  • Space moss phlox 18 to 24 inches apart.

How to Water and Feed Moss Phlox

  • Moss phlox grows in soil that is just moist, not wet; water moss phlox occasionally after it is established. Moss phlox does not like heat or drought.
  • Moss phlox does not require fertilizing.

Moss Phlox Care

  • Cut moss phlox back to encourage dense growth and continued flowering.
  • Moss phlox is susceptible to spider mites in hot, dry conditions. It is susceptible to root rot in wet winter conditions.

Moss Phlox Propagation

  • Phlox subulata seeds will germinate in 5 to 10 days at 60-65°F (16-18°C)

Moss Phlox Varieties to Grow

  • Phlox nana grows well in the arid Southwest.
  • ‘Amazing Grace’ bears pale pink flowers with pinkish-purple eyes.
  • ‘Apple Blossom’ bears pale lilac flowers.
  • ‘Candy Stripe’ has bicolored flowers of white and pink.
  • ‘Emerald Blue’ has light blue flowers.
  • ‘May Snow’ and ‘White Delight’ has white flowers.
  • ‘Red Wings’ has crimson flowers.


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