Creeping phlox

Creeping phlox: how do you recognise it?

Habit

Low mat about 15 cm high and 50 cm wide or more, with creeping runners (stolons) that root along the ground.

Leaves

Oval to oblong, 2–5 cm long, fresh green and mostly evergreen; the flower stems carry smaller leaves.

Flower

Round, five-petalled flowers of about 2 cm in loose clusters on upright stems of 15–20 cm, in April and May.

Colour

Lilac, lavender-blue, pink or white, depending on the cultivar.

Roots

Shallow and fibrous, with rooting runners; the plant gradually spreads this way.

Flowering: April–May · Plants: March–April and September–October · Pruning: May

Why grow it?

• Flowers in April and May in the shade, where few other ground covers bloom so freely.
• Quickly forms a dense mat that suppresses weeds and fills bare patches under shrubs.
• The foliage stays mostly green in winter, so the soil is covered all year round.
• Bees and bumblebees find nectar on the flowers in spring.
• Fully hardy (to about −30 °C) and easy to propagate from its runners.

Creeping phlox: where does it grow best?

• Part shade to light shade, for example under shrubs or trees with an open canopy. In full sun only if the soil stays moist.
• Loose, humus-rich loam or clay, acid to neutral. The soil must hold moisture without being waterlogged.
• Normally moist: do not let the soil dry out completely in summer.
• Lovely among ferns, under shrubs, along a shady path or at a woodland edge.
• Allow 30–40 cm per plant; the mat closes up within a few years.

Light

Partial shade and shade

Soil type

Loam or clay

Acidity

Acid or neutral

Moisture

Normal

Size

0.15 m tall, 0.5 m wide

Hardiness

Hardy (to -30 °C)

Goes well with

• Ferns: A fresh, green backdrop in the same part shade.
• Hosta: Large leaves beside the low, fine mat.
• Foamflower: Flowers at the same time with white plumes and has attractive foliage.
• Barrenwort: Another ground cover for dry shade, with fine spring flowers.
• Lungwort: Flowers in spring in blue and pink.

Creeping phlox: when and how to plant it?

Plant in March–April and September–October.

1. Plant in March–April or in September–October, when the soil is neither frozen nor waterlogged.
2. Work compost or leaf mould into the soil, especially if it is heavy or poor.
3. Dig a hole as deep as the pot and a little wider, and set the plant at the same depth as in its pot.
4. Space plants 30–40 cm apart.
5. Water straight away and keep the soil slightly moist for the first weeks.
6. Spread a thin layer of leaf mould around the plants, keeping the crown clear.

Care

Watering

Keep the soil slightly moist, especially in the first year and in dry summers. Water at the base, not over the foliage.

Feeding

A layer of compost or leaf mould in spring; more is rarely needed.

Mulching

A thin layer of leaf mould in spring keeps the soil cool and moist.

Spent flowers

Cut off the flower stems after flowering: this keeps the mat tidy.

Runners

In spring, cut off runners that travel too far and replant them elsewhere or give them away.

Tip: Plant it in loose, humus-rich soil and cut off the flower stems after flowering. For a denser mat, cut off rooted runners and replant them in a new spot.

Creeping phlox: when to prune it?

Pruning months: May.

When: After flowering, in May.

How:

• Cut the faded flower stems down to the foliage with shears.
• If the mat has become too large or too loose, trim it lightly back to about half its height.
• Cut off or pull out runners that you do not want.

Caution: Do not cut the evergreen foliage to the ground in autumn: it protects the plant in winter.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Runners

After flowering or in September: cut off rooted runners with some roots and replant them elsewhere straight away. The easiest and surest method.

Cuttings

In May–June: 5–8 cm cuttings from non-flowering runners, lower leaves removed, in moist, sandy potting compost. Keep them moist and out of full sun; they root in a few weeks.

Creeping phlox: how does it get through the winter?

Hardy to −30 °C.

• Fully hardy, to about −30 °C: no protection is needed in Belgium.
• The foliage stays green. In autumn, remove fallen leaves from the mat: a thick, wet layer can make the foliage rot.
• In a pot: use humus-rich, free-draining soil, put the pot in shelter and do not let the soil dry out completely.

Diseases and pests

• Powdery mildew: White powder on the foliage, especially in dry, stuffy spots. Give it more space, water at the base and cut off affected parts.
• Slugs: Young shoots and flowers get nibbled. Collect them in the evening and protect young plants.
• Spider mite: In a hot, dry summer the foliage turns dull with fine webbing. Spray with water and keep the soil moist.
• Drying out: Brown edges and a thinning mat in summer. Water and mulch.

Through the year

• March: Plant. Apply compost.
• April: Flowering begins. Plant.
• May: Full flower. After flowering, cut off the flower stems. Cut off runners.
• June: Take cuttings from non-flowering runners.
• July: Water in dry weather. Watch for spider mite.
• September: Plant or divide.
• October: Plant. Remove fallen leaves from the mat.
• December: Rest. The mat stays mostly green.

Good for wildlife

Bees

Nectar and pollen for honeybees and wild bees.

Did you know?

• The species name stolonifera means ‘bearing runners’: the plant spreads by overground runners.
• In the wild it grows in moist woodland in the Appalachians, in the east of North America.
• Every rooted runner can become a new plant, so one plant soon fills a whole edge.