Narrow-leaved lungwort

Narrow-leaved lungwort: how do you recognise it?

Habit

Low, loose clump about 25 cm tall and 40 cm wide, with a creeping rootstock.

Foliage

Narrowly lance-shaped, 15–30 cm long, rough and hairy, fresh green and unspotted. Appears after flowering and may partly die back in a dry summer.

Flowers

Funnel-shaped flowers of about 1.5 cm in small clusters, from March to May.

Colour

Pink in bud, then deep blue; ‘Azurea’ has a bright gentian-blue shade.

Roots

Creeping, fibrous and shallow rootstock; it transplants well.

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

Why grow it?

• Flowers from March, when there is still little food for bees and bumblebees.
• Deep blue flowers are rare in early spring and look lovely with yellow daffodils.
• The narrow, unspotted leaves are a calm backdrop for other spring flowers.
• Fully hardy to about −30 °C and faithful for years in the same spot.
• Slowly forms a ground-covering clump under deciduous shrubs.
• Little work: some compost and one cutting back is enough.

Narrow-leaved lungwort: where does it grow best?

• Half shade or light shade, for example under deciduous shrubs and trees.
• Humus-rich, moisture-retentive soil: loam or clay, acid to neutral.
• Simply moist soil: not too dry and not waterlogged.
• Sheltered from the fierce sun and from drying winds.
• Allow 30–40 cm per plant; in groups of 3–5 it forms a carpet fastest.

Light

Partial shade and shade

Soil type

Loam or clay

Acidity

Acid or neutral

Moisture

Normal

Size

0.25 m tall, 0.4 m wide

Hardiness

Hardy (to -30 °C)

Goes well with

• Hellebore: Large flowers and sturdy foliage in the same half shade.
• Daffodil: Yellow daffodils with blue flowers make a classic spring duo.
• Snowdrop: Flowers just before the lungwort and together they make a white and blue spring garden.
• Hosta: Comes up late and takes over after the lungwort has flowered.
• Male fern: Fresh green fronds that fill the space later in the year.

Narrow-leaved lungwort: 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 too wet.
2. Dig a hole as wide as the root ball and mix in a few spadefuls of compost or leaf mould.
3. Set the plant at the same depth as in its pot and firm the soil well.
4. Leave 30–40 cm between plants; plant in groups of 3–5.
5. Water in generously straight away, even if it is raining.
6. Spread a thin layer of leaf mould as mulch around the plants, without covering the crown.

Care

Water

Keep the soil moist, especially in the first year and in dry summers. Limp leaves are a sign of drought.

Feeding

A thin layer of compost or well-rotted organic fertiliser in spring.

Mulching

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

Spent flowers

Cut off faded clusters, unless you want seed.

Cutting back

Cut old, tatty leaves back to the ground after flowering, in June: fresh, clean foliage will follow.

Tip: Plant it under deciduous shrubs near spring bulbs: the narrow leaves keep the ground covered when the bulbs disappear. Cut the old leaves back after flowering to get fresh foliage.

Narrow-leaved lungwort: when to prune it?

Pruning months: June.

When: In June, after flowering, when the old leaves become untidy or mildewed.

How:

• Cut faded flower stems and the old leaves down to just above the ground.
• Use sharp scissors or secateurs and do not cut into the new leaf rosettes.
• Water afterwards and add some compost so the fresh foliage grows quickly.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Division

Divide older clumps after flowering, in May–June, or in September–October. Lift the plant, split it into pieces with roots and leaves, and replant them straight away in moist soil.

Seed

Sow fresh seed in summer or autumn in a tray of seed compost and put the tray outside in the cold. Seedlings appear in spring and flower after 2–3 years. Cultivars such as ‘Azurea’ do not always come true from seed.

Narrow-leaved lungwort: how does it get through the winter?

Hardy to −30 °C.

• Fully hardy, to about −30 °C: no protection is needed in Belgian winters.
• The foliage may largely die back in winter; leave it in place as protection until spring.
• In a pot: choose a frost-proof pot and do not let the soil dry out.

Diseases and pests

• Powdery mildew: White powder on the leaves, especially in dry weather. Water at the base, cut off affected leaves in June and leave space between plants.
• Slugs: Holes in the young leaves. Collect them in the evening and clear hiding places.
• Drought stress: Limp leaves with brown edges in a dry summer. Water generously and lay a little mulch.
• Leaf spot: Brown spots on the leaves in a wet summer. Cut off affected leaves; fresh foliage will grow.

Through the year

• March: Flowering begins. Plant. Give compost.
• April: Full flower. Plant.
• May: Flowering ends. Divide.
• June: Cut back old leaves. Water.
• July: Water in dry weather.
• September: Plant or divide.
• October: Plant. Mulch with leaf mould.
• November: Leave fallen leaves as protection.

Good for wildlife

Bees

Nectar and pollen for honeybees and wild bees.

Did you know?

• The species name angustifolia means ‘narrow-leaved’, after its narrow leaves.
• The flowers are first pink and then turn blue. The colour change happens because the acidity of the cell sap changes as the flower matures.
• It flowers as early as March, when few other plants offer nectar: an important first food source for bumblebees.