Navelwort

Navelwort: how do you recognise it?

Habit

Low clump that gradually widens, 20–25 cm tall and 40 cm wide, with short rhizomes.

Foliage

Heart-shaped to oval, 8–15 cm, rough to the touch, dark green; evergreen in mild winters.

Flower

Loose sprays of five-petalled flowers of about 1 cm, from March to May.

Colour

Sky blue with a white eye; in ‘Starry Eyes’ with white stripes on the petals.

Roots

Short, creeping rhizomes by which the clump slowly widens.

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

Why grow it?

• Sky-blue flowers from March to May, at a time when little else is in flower.
• Bees and early bumblebees find pollen and nectar.
• The dark green foliage stays largely green and covers the ground in summer too.
• A good ground cover for the shade under shrubs and trees.
• Fully hardy and easy, as long as the soil stays moist.

Navelwort: where does it grow best?

• Partial shade to shade; it dislikes full sun and strong afternoon sun.
• Humus-rich, moisture-retentive loam or clay, acid to neutral.
• Evenly moist: it does not tolerate long drought, nor standing water.
• Plant 30–40 cm apart; as ground cover, in groups of five to nine per square metre.

Light

Partial shade and shade

Soil type

Loam or clay

Acidity

Acid or neutral

Moisture

Normal

Size

0.2 m tall, 0.4 m wide

Hardiness

Hardy (to -25 °C)

Goes well with

• Lenten rose: Hellebores flower at the same time and share the same partial shade.
• Primrose: Yellow or pink primroses next to the sky blue.
• Ferns: Fresh green foliage that frames the clump all season.
• Daffodil: Yellow spring bulbs rise above the low blue carpet.

Navelwort: 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 not frozen or too wet.
2. Dig a hole twice as wide as the root ball and mix in plenty of leaf mould.
3. Set the plant at the same depth as in its pot and firm the soil.
4. Keep 30–40 cm between plants; a little closer as ground cover.
5. Water in generously at once and lay a layer of leaf mould around the plants.

Care

Water

Keep the soil moist, especially in the first year and in spring during flowering; water in summer in dry weather.

Feeding

A thin layer of compost in spring is enough.

Mulching

A layer of leaf mould in autumn keeps the soil moist and feeds the plant.

Tidying

In February–March, remove faded, damaged leaves so the fresh foliage and flowers show well.

Dividing

Rejuvenate an old clump every few years by dividing it.

Tip: Give it humus-rich soil in partial shade and keep the soil moist in summer. In February–March, remove the oldest leaves: this keeps the clump fresh.

Navelwort: when to prune it?

Pruning months: February–March.

When: It is hardly pruned. In February–March, cut away the old, damaged foliage, before flowering.

How:

• Cut damaged or frost-burnt leaves to just above the ground.
• Remove dead pieces from the centre of the clump.
• After flowering, you can cut off the faded flower sprays if you want a tidy clump.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Division

After flowering (June) or in September: lift the clump, divide it into pieces with roots and replant at once in moist soil.

Seed

Sow fresh seed in summer outdoors in a seed tray in partial shade; it germinates slowly, sometimes only the following spring.

Navelwort: how does it get through the winter?

Hardy to −25 °C.

• Hardy down to about −25 °C: no protection is needed in Belgian winters.
• The foliage stays green in mild winters; in hard frost it may be damaged and regrows in spring.
• In a pot: use a humus-rich compost and put the pot in a sheltered spot; do not let it dry out.

Diseases and pests

• Slugs: Holes in young leaves in spring. Collect them in the evening or lay a ring of coarse grit around the plant.
• Scorched leaves: Brown edges in full sun or drought. Give shade and water, and cut off the damaged leaves.
• Powdery mildew: White powder on the leaves in dry shade. Mulch, water, and cut off affected leaves.
• Root rot: Yellow, limp clump where water stands. Improve drainage or move the plant.

Through the year

• February: Cut away old, damaged leaves.
• March: First flowers. Plant or divide. Add compost.
• April: Full flower. Plant.
• May: Last flowers. Water in dry weather.
• June: Cut off faded sprays. Divide if wanted.
• July: Water in dry weather. Check the mulch.
• September: Plant or divide.
• October: Plant. Leaf mould as mulch.

Good for wildlife

Bees

Nectar and pollen for honeybees and wild bees.

Did you know?

• The name Omphalodes comes from the Greek word for navel and refers to the shape of the little nutlets.
• The cultivar ‘Cherry Ingram’ is named after Collingwood ‘Cherry’ Ingram, an English gardener and lover of ornamental cherries.
• It belongs to the borage family, like forget-me-not and borage; its flowers closely resemble those of forget-me-nots.