Harebell

Campanula rotundifolia

In other languages: Grasklokje (Nederlands) · Campanule à feuilles rondes (Français)

Harebell is a native perennial of poor grassland, heath, dunes and verges throughout Europe, including Belgium. From June to September fine, nodding bells in pale blue to violet-blue hang from thin, wiry stems 20–30 cm tall. The round leaves at the base, which give the plant its scientific name, have often disappeared by flowering time; the stem leaves are narrow and grass-like. Gardeners love its natural, airy look in a heath or meadow planting, a rock garden or between paving stones. It is extremely hardy and needs almost no care, as long as the soil stays poor.

Updated on 9 October 2026

Light
Sun or partial shade
preferably some sun
Moisture
Dry to normal
no wet feet
Legal basis
Sand or loam
any pH
Hardiness
Fully hardy
down to -40 °C
Size
0.3 m
tall, 0.2 m wide
Flowering
June–September

Key facts
Pruning months	March
Height	0.3 m
Native to Belgium	Yes
Good for bees, butterflies and birds	Yes, for bees
Poisonous to people and pets	Not known to be poisonous
Flowering	June–September

Identify

Harebell: how do you recognise it?

Habit: Airy, loose clump 20–30 cm tall and 20 cm wide, slowly spreading by thin rhizomes and by seed.
Leaves: Small, round to heart-shaped leaves at the base; narrow, grass-like leaves along the stems.
Flower: Nodding bells 1.5–2 cm long, pale blue to violet-blue, rarely white, from June to September.
Stems: Wiry and flexible: the flowers dance in the wind.
Roots: Fine, creeping rhizomes.

Flowering: June–September · Sowing: March–April · Plants: March–April and September–October · Pruning: March

In your garden

Why grow it?

A native plant that feeds wild bees from June to September.
A long season: four months of fine blue bells.
Ideal for poor, dry soil, where few other flowering plants do well.
Suits a heather garden, rock garden, gravel garden or flower meadow.
Extremely hardy and very little work.

Harebell: where does it grow best?

Sun or part shade; in full sun it stays more compact and flowers more freely.
Poor, free-draining sandy or loamy soil, acid to chalky.
Dry to moist; no fertiliser and no heavy, wet soil.
Plant 20 cm apart, in groups of five or more for a good effect.
Choose a spot without strong competitors: on rich soil other plants crowd it out.

Light: Sun and partial shade
Soil type: Sand or loam
Acidity: Not fussy
Moisture: Dry or normal
Size: 0.3 m tall, 0.2 m wide
Hardiness: Hardy (to -40 °C)

Goes well with

Wild thyme: Low, fragrant cushions on the same poor, dry soil.
Blue fescue: Fine, blue-grey tufts with the bells dancing between them.
Carthusian pink: Bright pink flowers on slender stems, in the same sunny spot.
Yarrow: Flat white flower heads, also native and drought tolerant.
Heather: On acid soil, a classic heathland pairing.

Maintenance

Harebell: when and how to plant it?

Plant in March–April and September–October.

Plant in March–April or in September–October.
Loosen the soil, but do not mix in compost or fertiliser.
On heavier soil, mix in some coarse sand or gravel.
Set the young plants at the same depth as in their pots, 20 cm apart.
Water straight away and keep the soil slightly moist for the first few weeks.
Do not use a compost mulch; a thin layer of gravel or sand is fine.

Care

Water: Water young plants only in dry spells; after that it is no longer needed.
Feeding: Never: fertiliser makes it floppy and helps its competitors.
Spent flowers: Leave them if you want it to self-seed; otherwise cut them off for a longer display.
Weeding: Keep vigorous grasses and weeds away from young plants.
Mowing: In a flower meadow, mow only after flowering, at the end of September or in October.

Tip: Give it a poor, dry spot and never any fertiliser: the poorer the soil, the better it holds its own against other plants.

Harebell: when to prune it?

Pruning months: March.

When: It needs hardly any pruning. In March, cut away the old, dry stems.

How:

In March cut the dead stems back short, just above the young leaves.
In summer you can cut off faded stems for a tidier plant and a longer display.
Leave some of the seed capsules if you want seedlings.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Seed: In March–April, indoors or outdoors: scatter the dust-fine seed on moist compost without covering it, as it needs light to germinate. Keep the compost moist and plant out the seedlings when they are big enough.
Division: In March–April or in September: lift small pieces of the clump with roots and replant them straight away.

Harebell: how does it get through the winter?

Hardy to −40 °C.

Extremely hardy, to −40 °C: no protection is ever needed in Belgium.
The top growth largely dies back; it reshoots in spring.
Heavy, wet soil in winter is its worst enemy: make sure drainage is good.

Diseases and pests

Slugs: They eat the young shoots and flowers. Pick them off in the evening; on dry, poor soil there are fewer.
Crowded out: On rich soil, grasses and strong plants grow over it. Do not feed and remove competitors.
Rotting: On wet soil the roots rot. Plant it in a drier, sandier spot.
Floppy stems: In a spot that is too rich or too shady the stems fall over. Give more sun and no fertiliser.

Through the year

March: Cut away old stems. Sow indoors or outdoors. Plant.
April: Sow and plant. Watch for slugs.
May: Plant out seedlings. Weed.
June: Flowering begins.
July: Full bloom. Wild bees in the bells.
August: Flowering. Cut off faded stems if you like.
September: Last flowers. Collect seed. Plant.
October: Plant. Mow a flower meadow.
December: Rest.

Use

Good for wildlife

Bees: Nectar and pollen for honeybees and wild bees.

You and this species

Did you know?

In Scotland it is called bluebell, whereas in England that name means the wild hyacinth.
Although it is called rotundifolia (round-leaved), the round leaves at the base have usually gone by flowering time.
Some wild bees collect pollen only from bellflowers and so depend on plants like this one.

Garden plants · All species