Introduction

The plant goes unnoticed during the year because it blends in with the grass and other surrounding parts of the landscape until flowers emerge in late winter and spring (Fig. 1). It is one of the signals that spring has arrived. Flower colors vary from red and lavender to pink and white, depending on the cultivar grown. Plants grow no more than about 6 inches tall, forming thick clumps and a good ground cover. The stiff leaves are narrow, growing to about an inch long and perhaps to 1/16 inch wide.

General Information

Scientific name: Phlox subulata

Pronunciation: flocks sub-yoo-LAY-tuh

Common name(s): creeping phlox, moss pink, moss phlox

Family: Polemoniaceae

Plant type: perennial; annual; herbaceous

USDA hardiness zones: 3B through 10 (Fig. 2)

Planting month for zone 7: Jun; Jul

Planting month for zone 8: May; Jun; Jul

Planting month for zone 9: Apr; May; Jun; Jul; Aug

Planting month for zone 10: Feb; Mar; Apr; May; Jun; Jul; Aug; Sep; Oct; Nov; Dec

Origin: native to North America

Uses: ground cover; cascading down a wall

Availability: generally available in many areas within its hardiness range

Description

Height: .5 to 1 feet

Spread: depends upon supporting structure

Plant habit: spreading; prostrate (flat)

Plant density: moderate

Growth rate: moderate

Texture: fine

Foliage

Leaf arrangement: alternate

Leaf type: simple

Leaf margin: entire

Leaf shape: linear

Leaf venation: none, or difficult to see

Leaf type and persistence: deciduous

Leaf blade length: less than 2 inches

Leaf color: green

Fall color: not applicable

Fall characteristic: not applicable

Flower

Flower color: pink; lavender; white; red

Flower characteristic: spring flowering

Fruit

Fruit shape: unknown

Fruit length: unknown

Fruit cover: unknown

Fruit color: unknown

Fruit characteristic: inconspicuous and not showy

Trunk and Branches

Trunk/bark/branches: not applicable

Current year stem/twig color: reddish

Current year stem/twig thickness: thin

Culture

Light requirement: plant grows in part shade/part sun

Soil tolerances: acidic; alkaline; sand; loam; clay

Drought tolerance: moderate

Soil salt tolerances: poor

Plant spacing: 12 to 18 inches

Other

Roots: not applicable

Winter interest: no special winter interest

Outstanding plant: not particularly outstanding

Invasive potential: aggressive, spreading plant

Pest resistance: long-term health usually not affected by pests

Use and Management

Creeping phlox is suitable for rock gardens, ground covers, or for planting on top of a garden wall. Flowers and foliage will cascade down a container side, making a nice complement to an upright plant in the container. It makes a nice stabilizer for a sloping landscape.

Phlox should be located in the full sun for best growth. The plants benefit from fertilization and from regular irrigation in dry weather during the growing season. Cut the foliage back after flowering to encourage denser growth and perhaps a weak second flower display.

Cultivars include 'Crimson Beauty'—red flowers; 'Emerald Cushion'—pink flowers; 'Millstream'—white with a crimson eye; 'Millstream Daphne'—dark blue flowers; 'White Delight'—white flowers.

Propagation is by division of non-woody stems in early spring. Stem cuttings may be taken in summer or fall.

Pests and Diseases

Mites cause the foliage to lose its green color, especially in dry weather. Heavy infestations form fine webbing.

Leaf spots attack the leaves. Remove infected leaves as you notice them.

Powdery mildew is the most common disease on this plant. The disease causes a white powdery growth on the leaves.

Crown rot may cause rotting near the soil line. A white fungal growth forms on the stem bases. Remove infected plants.