Heath Milkwort.

At a glance

Care level

Moderate

Plant type

Perennial

Light

Partial shade to full sun

Indoor light

Bright indirect

Water

Every 3 to 7 days

Mature size

15 cm

Growth rate

Slow

Hardiness

USDA 7 to 9

Bloom time

Late spring to mid summer

Care

Keep the soil consistently moist but never waterlogged to mimic its natural boggy habitat. Watch for wilting if the soil dries out too much, as it doesn't handle drought well. It thrives best when it has plenty of space to spread without competition from taller plants.

Watering

Keep the soil evenly moist at all times.

Feeding

Use a light, balanced organic feed during the growing season.

Pruning

Trim back dead stems in early spring to encourage fresh growth.

Repotting

Repot only when the plant has clearly outgrown its container.

Soil

Acidic, peaty, well drained

Soil pH

Acidic

Temperature

-15 to 25°C

Humidity

50 to 80%

Safety

People

There is no significant toxicity reported for humans, but it is not intended for consumption.

Children

Keep away from small children as the plant is not meant for ingestion.

Edibility

This plant is not considered edible and should not be consumed.

How to identify it

• Small opposite leaves
• Tiny blue or white flowers
• Low growing creeping habit
• Found in acidic soil

Height

0.05 to 0.2m

Spread

0.1 to 0.3m

Leaves

green, evergreen

Flowers

blue, purple, white, 0.5 to 1cm

Problems to watch for

• Root rot · Occurs when soil remains waterlogged for too long.

Growing it

Propagation

seed, cuttings

When to plant

spring, autumn

Plant it with other acid loving, low growing species to create a naturalistic heathland carpet.

Grows well with

• Common Heather · They share similar requirements for acidic, well drained soil.
• Heath Bedstraw · It naturally grows alongside this species in heathland habitats.

Similar species

• Common Milkwort · It is closely related but typically grows in slightly more neutral soils.

Science

Family

Polygalaceae

Genus

Polygala

Order

Fabales

Class

Magnoliopsida

Native range

Western and Central Europe

Conservation

It is common in its native range and not currently of conservation concern.

It is a characteristic species of nutrient poor, acidic grasslands and heathlands where it competes well by staying low to the ground.

Value to wildlife

nectar source

Pollinators

bees, butterflies

Uses

rock gardens, heathland restoration, ground cover

Taxonomy resolved against GBIF.

Questions people ask

Does it need full sun?

It prefers partial shade to full sun but needs consistent moisture.

Can I grow it in a pot?

It is best suited for rock gardens or open ground rather than containers.

Where the name comes from

The name Polygala is derived from the Greek words polys, meaning much, and gala, meaning milk. The specific epithet serpyllifolia refers to the resemblance of its leaves to those of wild thyme, Thymus serpyllum.

Good to know

• The name Polygala comes from Greek words meaning much milk, as it was once thought to increase milk production in cattle.
• It thrives in acidic, nutrient poor soils where many other plants struggle.
• The flowers are zygomorphic, meaning they have a distinct bilateral symmetry.