Creeping phlox

Sun

Full sun gives the best flowering. Tolerates light shade, but flowers less densely.

Water

Water regularly while establishing, allowing the soil surface to dry between waterings. Established plants tolerate short dry spells; water during prolonged drought, especially in shallow soil or containers.

Soil

Well-drained sandy, gravelly or loamy soil with modest fertility. Tolerates a range of soil pH, but struggles in heavy, persistently wet ground.

Height

0.3-0.5 ft (0.1-0.15 m)

Spread

1-2 ft (0.3-0.6 m)

Flowers

Mid- to late spring; pink, rose, purple, lavender, blue-lilac or white, depending on cultivar. Some flowers have contrasting eyes or striped petals.

Foliage

Evergreen. Small, narrow, pointed green leaves form a dense, moss-like carpet. Foliage may bronze or suffer some dieback in severe winters.

Growth

Moderate; creeping stems gradually form a broad mat.

Care needed

Low

• Water new plants at soil level whenever the root zone begins to dry; avoid keeping the ground constantly wet.
• Do not feed routinely in ordinary garden soil. On very poor soil, apply a light balanced feed in spring.
• Use a thin gravel mulch around plants if needed; keep compost, bark and fallen leaves off the crowns.
• Pull weeds while plants are young, before the mat closes over the soil.
• Renew thinning plants with rooted outer sections or cuttings rather than trying to revive a bare, woody centre.

Pruning. Immediately after flowering, lightly shear off spent flowers and a little leafy growth to keep the mat compact. Retain green foliage and avoid cutting deeply into bare, woody stems.

Early spring

Remove trapped leaves and check for winter rot; trim away dead shoots once healthy growth is visible.

Spring

Plant in a sunny, freely draining position and water thoroughly.

Late spring

After flowering, lightly shear the mat to remove spent blooms and encourage branching.

Summer

Water during prolonged drought and inspect hot, dry patches for spider mites.

Summer

Take non-flowering shoot cuttings to replace ageing plants or extend a planting.

Early autumn

Divide rooted outer sections where needed, allowing time for establishment before winter.

Late autumn

Clear fallen leaves from the mat and keep drainage channels open.

• Let it spill over a low retaining wall to soften the edge with spring colour.
• Plant broad patches on a sunny, well-drained bank, with dwarf bulbs emerging through or beside them.
• Edge gravel paths with low cushions, keeping plants outside areas that receive foot traffic.
• Combine it with dwarf conifers, rock roses and stonecrop in a rock garden for contrasting textures.

Garden styles it suits: Alpine rock garden, Dry gravel garden, Cottage garden, Pollinator garden, Low-maintenance and Mountain lodge.

Plant it with: Candytuft, Basket-of-gold, Rock cress, Dwarf bearded iris, Grape hyacinth and Stonecrop.

Wildlife: Spring flowers provide nectar for butterflies and other pollinating insects. Deer usually leave it alone, although browsing is still possible.

• Crown or root rot in wet soil: improve drainage or move plants to a raised, gravelly position; discard badly rotted plants.
• Spider mites in hot, dry weather: look for fine webbing and pale, stippled leaves; rinse foliage thoroughly, including undersides, and avoid severe drought stress.
• Bare, woody centres in older mats: replace the centre with healthy rooted outer pieces or new plants raised from cuttings.
• Sparse flowering in shade: move to a sunnier position and avoid excessive nitrogen feeding.

Not known to be toxic to cats, dogs, horses or people; no part is recognised as poisonous. It is not a food plant, and eating plant material may still cause mild stomach upset.

• Creeping woodland phlox (Phlox stolonifera)

  Has broader, oval leaves and flowers held on noticeably upright stems above a creeping leafy mat. It prefers woodland conditions rather than the sunny, dry sites suited to moss phlox.

• Rock soapwort (Saponaria ocymoides)

  Also trails over rocks with pink spring flowers, but has broader oval leaves and loose, branching flower clusters rather than a tight carpet of needle-like foliage.

Phlox comes from the Greek word for flame, while subulata means awl-shaped, referring to the narrow, pointed leaves.

Propagation. Take non-flowering shoot cuttings in summer, or separate rooted outer sections in spring or early autumn. Named cultivars should be propagated vegetatively to retain their flower colour and form.

Accepted botanical name

Phlox subulata

In the US and Canada

Native in Canada and the lower 48 states. Introduced in Canada.

Native range

Arkansas, Connecticut, Delaware, Georgia, Indiana, Iowa, Kentucky, Louisiana, Maine, Manitoba, Maryland and Masachusettes.

Measured

Soil pH 5.7 to 7.5.

Sources: GBIF (CC BY 4.0), USDA PLANTS and Trefle (CC BY 4.0). The care and design notes are LandscapeGPT's own.