Ninebark

Ninebark: how do you recognise it?

Habit

Shrub of 2–3 m with upright, later gracefully arching branches.

Leaf

Alternate, 4–8 cm, round to oval, three-lobed and irregularly double-toothed; green, or dark purple or yellow in the garden forms.

Bark

Brown bark that peels in long strips and layers on older branches.

Flower

Domed heads of small, white to pale pink flowers with conspicuous stamens, in June.

Fruit

Clusters of inflated, red to brown pods in summer.

Difference from guelder rose

Guelder rose has opposite leaves and large white outer florets.

Difference from smoke-tree

The smoke-tree has untoothed, round leaves and plumes like puffs of smoke.

Flowering: June · Pruning: June–July

Identify by feature: Palmate leaves

Looks like it, but isn’t

• Guelder rose Viburnum opulus: opposite leaves and large white outer florets. Difference from guelder rose
• Smoke-tree Cotinus coggygria: untoothed, round leaves and plumes like puffs of smoke. Difference from smoke-tree

Why grow it?

• Colourful foliage, dark purple or golden yellow, from spring to autumn.
• Domed white flower heads in June for bees and hoverflies.
• Grows almost anywhere: sun or partial shade, wet or dry soil.
• Strong and fast-growing: suitable for an informal hedge or a colourful border.

Ninebark: where does it grow best?

• Sun to partial shade; in sun the leaves colour best, in shade purple and yellow forms turn greenish.
• Any soil, from sand to clay, wet or dry.
• Allow 2–2.5 m width; compact cultivars stay around 1–1.5 m.
• Lovely in a mixed border, as an informal hedge or as a splash of colour among green shrubs.

Light

Sun or partial shade

Legal basis

Any garden soil

Moisture

Dry to wet

Size

2.5 m tall, 2.5 m wide

Hardiness

Throughout Belgium, no protection needed

Goes well with

• White dogwood: Also for wet soil: variegated leaves next to dark purple, and red twigs in winter.
• Guelder rose: White flowers in May–June and red berries, on the same moist soil.
• Spiraea: A yellow-leaved Japanese spiraea in front, for a border full of leaf colour.

Good and bad companions

Goes well with

• Suits the woodland edge or the light shade of: ginkgo, box elder, ash, honey locust, field maple, silver maple

Ninebark: when and how to plant it?

1. Plant from November to March; pot-grown plants all year round, except in frost or drought.
2. For an informal hedge: 1–2 plants per metre.
3. Plant at the same depth as in the pot and firm the soil well.
4. Water generously after planting and in dry spells during the first year.

Care

Watering

In dry spells during the first year; hardly at all after that.

Feeding

A little compost in spring is enough.

Leaf colour

Young shoots have the brightest colour: thin out some old wood every year.

Airy spot

Give it space and sun: in a stuffy corner it is more prone to powdery mildew.

Tip: Combine a purple and a yellow form, such as ‘Diabolo’ and ‘Dart’s Gold’: together they give colour all summer. For a small shrub, choose a compact cultivar such as ‘Little Devil’.

Ninebark: when to prune it?

Pruning months: June–July.

When: After flowering (July).

How:

• Every year, cut a few of the oldest branches off at the base; this keeps the shrub young and colourful.
• Cut flowered stems back to a strong young shoot lower down.
• A neglected shrub can be cut right back to 20–30 cm above the ground; if you do this in late winter, it will not flower that year.

Caution: Do not prune in winter if you want flowers: it flowers on last year’s wood.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Semi-ripe cuttings

In June–July, take semi-ripe cuttings of 10–15 cm and root them in a pot of cutting compost under plastic.

Hardwood cuttings

In winter, push 20 cm lengths of young branches into the ground; they usually root by summer.

Ninebark: how does it get through the winter?

Hardy throughout Belgium: no protection needed.

• Fully hardy.
• In winter the peeling brown bark of the older branches catches the eye.

Diseases and pests

• Powdery mildew: White coating on the leaves in summer, especially on purple forms. Give it an airy, sunny spot and thin out the shrub.
• Aphids: Aphids on the young shoot tips in spring; natural predators usually deal with them.
• Greenish leaves: Purple and yellow forms turn green in shade. Plant them in sun.
• Bare at the base: Without pruning it goes bare at the base. Cut a few old branches off at the base every year.

Through the year

• March: Planting; add a little compost.
• April: The coloured leaves unfurl.
• June: Flowering: domed white heads; prune as soon as flowering is over.
• July: Prune after flowering: remove old branches; take semi-ripe cuttings.
• August: Red, inflated fruits; water in dry spells.
• November: Planting and taking hardwood cuttings.

What can you use it for?

Garden and landscape

Strong, easy shrub for colour in a border or an informal hedge; also on wet ground.

For wildlife

Bees and hoverflies visit the flowers.

Did you know?

• In English it is called ‘ninebark’: the bark of old branches peels off in countless layers.
• The name ninebark refers to the bark of old branches, which peels off in countless layers.
• Physocarpus means ‘bladder fruit’, after the inflated fruits.
• ‘Opulifolius’ means ‘with leaves like Viburnum opulus’, the guelder rose.