Box

Box: how do you recognise it?

Habit

Dense evergreen shrub of 1–5 m; in gardens usually kept low as a hedge, ball or topiary.

Leaf

Opposite, 1–2.5 cm, oval, untoothed and leathery; paler underneath.

Bark

Young shoots green and square; the wood is very hard and yellow.

Flower

Inconspicuous, fragrant, yellowish-green flowers in March–April.

Fruit

Small capsules with three little horns.

Difference from garden privet

Garden privet has larger leaves, white flower panicles and black berries.

Flowering: March–April · Pruning: May–June and August–September

Identify by feature: Evergreen leaves

Looks like it, but isn’t

• Garden privet Ligustrum ovalifolium: larger leaves, white flower panicles and black berries. Difference from garden privet

Why grow it?

• Evergreen and fine-leaved: the classic low hedge, ball or topiary shape.
• Tolerates sun, partial shade and even shade.
• Can be clipped very precisely and keeps its shape for years.
• The fragrant flowers in March–April are early food for bees.

Box: where does it grow best?

• Sun, partial shade or shade; in full sun the leaves scorch more easily, especially just after clipping.
• Ideally chalky, free-draining soil that doesn’t dry out; no wet feet.
• An airy spot rather than a stuffy corner: the leaves dry quickly there and box blight has less of a chance.
• Suitable for low hedges and edging, balls in a border and pots on the patio.

Light

Sun to shade

Legal basis

Any garden soil

Moisture

Normal

Size

5 m tall, 1.5 m wide

Hardiness

Throughout Belgium, no protection needed

Goes well with

• English lavender: A box edging around lavender: the classic formal garden, green and grey with purple flowers.
• Yew: Taller yew hedges or cones behind a low box edging give structure, in winter too.
• Rosemary: In a herb garden, box forms the beds; rosemary, sage and thyme fill them.
• Roses: A box edging around a rose bed keeps it looking neat, even in winter.

Box: when and how to plant it?

1. Plant in March–April or September–October, root-balled or container-grown.
2. For a low edging hedge: 6–10 plants per metre, depending on their size (the smaller the plants, the closer together).
3. Dig a trench, mix in some compost and plant at the same depth as before.
4. After planting, lightly trim the tips: the plants branch better and the hedge closes up faster.
5. Buy only healthy plants without brown patches or bare areas, from a reliable nursery.

Care

Watering

Regularly in the first year, then during prolonged dry spells. Water at the base, not over the leaves.

Feeding

A little compost or organic fertiliser in March–April.

Building a young hedge

Let the hedge gain only a few centimetres in height each year and keep the top slightly narrower than the base: it will stay dense right to the bottom.

Checking

From April to October, look deep inside the shrub every few weeks for caterpillars, webbing and feeding damage from box tree moth.

Hygiene

Clear up clippings and fallen leaves and disinfect your shears, especially when moving from one hedge to another.

Tip: Don’t just look at the outside: box tree moth caterpillars start in the heart of the shrub. Push the branches apart and look for webbing and small green droppings. Catch them early and you save the hedge.

Box: when to prune it?

Pruning months: May–June and August–September.

When: In May–June and in August–early September.

How:

• Clip in cloudy, dry weather: in bright sun the freshly cut leaves scorch, and wet leaves help box blight spread.
• Disinfect your shears before and during clipping to prevent box blight, and clear up the clippings straight away.
• Stretch a line to clip a hedge straight; a template helps for balls, but a practised eye works too.
• Stop clipping after early September: the new growth then has time to harden off before winter.

Caution: When clipping, look out for box tree moth caterpillars (green with black stripes) and their webbing.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Cuttings

In August–September, take 10–15 cm cuttings from healthy, semi-ripe shoots, strip the lower leaves and insert them in a mix of sand and potting compost. They root slowly but surely.

Box: how does it get through the winter?

Hardy throughout Belgium: no protection needed.

• Fully hardy.
• Frost, wind and winter sun can turn the leaves brown or bronze; they usually green up again in spring.
• In a pot: put it somewhere sheltered and water now and then in dry winter weather, as evergreens lose moisture in winter too.
• Box tree moth caterpillars overwinter in a silk cocoon between the leaves and become active again in spring.

Diseases and pests

• Box tree moth: Green caterpillars with black stripes strip the shrub from the inside, leaving webbing and small green droppings. There are several generations a year (April–October). Pick or vacuum off the caterpillars, or spray young caterpillars with a biological product based on Bacillus thuringiensis. Tits and sparrows are eating them more and more.
• Box blight: Brown spots, sudden leaf drop and black streaks on the shoots, or pinkish-orange spores on the leaves. Cut out affected parts generously, clear up fallen leaves and put everything in the general waste, not on the compost heap. Keep the foliage dry.
• Box sucker: Cupped, curled little leaves at the shoot tips in spring; mainly a cosmetic problem that disappears with the first clip.
• Repeated attacks: A hedge that declines year after year is better replaced. Japanese holly looks most like box but needs acid soil; yew is native and takes clipping just as well, but is poisonous too.

Through the year

• March: Planting can start again; add some compost.
• April: Box tree moth caterpillars become active: check the shrubs.
• May: First clip, late May, in cloudy weather.
• June: Clip if you didn’t manage in May; watch for a new generation of box tree moth.
• July: Check for box tree moth and box blight; water in dry spells.
• August: Second clip, from late August.
• September: Last clip by early September at the latest; take cuttings and plant.
• October: Planting; clear up clippings and fallen leaves.

What can you use it for?

Garden and landscape

The classic low hedge, ball or topiary shape.

Wood

Very hard, fine-grained wood for carving, chess pieces and instruments.

Caution: Poisonous. Box tree moth and box blight hit hard; consider alternatives such as Ilex crenata or yew.

Did you know?

• In Flanders box is called ‘palm’: the blessed sprigs on Palm Sunday are box. Box tree caterpillar and box blight make it vulnerable.
• In Flanders box is called ‘palm’: the blessed sprigs on Palm Sunday are box.
• The very hard, fine-grained wood was used for carving, chess pieces, musical instruments and wood engravings.
• Box tree moth comes from East Asia and has been spreading through Europe since the start of this century.
• The word ‘box’, like the Dutch bus, goes back to the Greek pyxis: a small box made of boxwood.
• Wood engravings, such as the illustrations in old books, were cut into the end grain of boxwood: it is hard and fine enough for the finest lines.