Box, Buxus sempervirens, is a British native tree, most commonly used for hedging. It’s synonymous with formal gardens, particularly parterres and knot gardens. In recent years, however, it has suffered the double whammy of box blight and box moth caterpillar, both of which weaken and can kill the plants. This means box is no longer the hedging plant of choice in some areas of the UK, and it’s best to grow alternatives to avoid these problems.
How to grow box
Grow box in moist but well-drained soil in full sun to partial shade. Prune regularly to keep in shape and keep an eye out for box blight and box moth caterpillar, both of which can harm the look and health of your box plants.
More on growing box:
Where to grow box
Box makes an excellent low-growing hedge and can also be used to make evergreen balls or topiary shapes to add evergreen winter interest to the garden. Plant box in moist but well-drained soil in full sun to partial shade.
How to plant box
Box plants are usually bought in pots and can therefore be planted at any time of year, as long as the ground isn’t frozen. Dig a generous hole, adding plenty of well-rotted compost and mycorrhizal fungi to give the plants a good start. Alternatively, buy bare-root box plats from autumn to spring. Soak them overnight before planting them at the same level they were planted in the field.
Follow Monty Don’s guide to planting box as a hedge, in this clip from Gardeners’ World:
Growing box: problem-solving
The biggest enemies of box are box blight and box moth caterpillar, which can decimate established hedges. Box blight is a fungal disease that causes leaf loss and ultimately weakens the plant. It’s difficult to treat once it has taken hold, however, you can manage it to reduce the damage if you catch it early on. Simply remove affected plants immediately and do not replant box in the same area.
Find out how to identify box blight and prevent its spread, in this clip from Gardeners’ World:
Here, Monty takes action to rescue his diseased box hedging. Armed with a hedge trimmer, he demonstrates how to cut out the blight-affected growth, explaining how and where to cut, and why this should help to save diseased box plants. Afterwards, he shows you how to clean your tools and what to do with your clippings to avoid spreading the blight spores to other unaffected box plants:
Box moth caterpillar is the larvae of the box moth, which feeds on box leaves. Native to East Asia, it has no known predators in Britain and therefore causes huge damage to its host plant. Signs to look out for include distinctive cobwebbing around the foliage and small eggs laid on the underside of leaves. Box moth caterpillar can be managed with pheromone traps. Caterpillars can also be picked off by hand if you can spot them.
How to propagate box
Box is easy to propagate by taking cuttings.
Follow Monty’s guide to taking box cuttings, below:
How to prune box
Trim box hedges from mid to late summer. However, if you are creating topiary, prune your shape initially in spring and then later in the summer.
Follow Monty’s guide to pruning box hedges, including how to keep them looking neat all winter:
Mulch box plants every year with well-rotted manure or compost.
Box varieties to try
- Buxus sempervirens – the common box is native to the British Isles and has small, evergreen leaves and a dense habit. It’s a popular choice for hedging and can be clipped into all manner of shapes for topiary.
- Buxus microphylla ‘Golden Triumph’ – one of the hardier cultivars of this Asian species, with slow growing, smaller leaves. Young foliage starts yellow, turning a yellowish green two-tone. It can be grown in full or partial sun and thrives in moist, yet well drained soil.
- Buxus sempervirens ‘Suffruticosa’ – this dwarf form is a slow growing, denser shrub than common box. It’s a good choice for low hedging and is commonly used for parterres and knot gardens.
- Buxus sempervirens ‘Blauer Heinz’ – a slow-growing box variety with blueish-green foliage. This plant is used for hedging and topiary, especially balls.
- Buxus sempervirens ‘Rocket’ – a fast-growing variety, with a narrow, upright habit that makes it a good choice for taller hedging.
- Buxus sempervirens ‘Elegans’ – a variegated type of box with a medium growth habit. Leaves have a creamy-silvery border.