A box hedge is a classic garden choice – and so versatile. You can’t just plant and go though; they need some special care. Find out what it takes.
15.09.2023
The hugely popular evergreen box – officially known as buxus sempervirens – is found in southwestern and central Europe, North Africa and western Asia. The plant is an enduring choice for many gardeners, in part due to its versatility as a hedge or standalone shrub. Box is also valued as an evergreen that brings a splash of colour to the garden and looks handsome all year round – as long as it gets the right care.
The familiar box shrub used for hedging is part of a large family of around 70 boxwood plant varieties. Its blossoms contain lots of nectar and pollen, making it particularly attractive to bees when in bloom.
If you intend to plant a box hedge in your own garden, it’s worth knowing that box is a little fussy about its neighbours: it is a good partner for plants with similar requirements, including tall-growing perennials such as hydrangea or delphinium, but does not thrive quite as well when planted beside sun-loving herbs and shade plants. Just note that in the latter situation a box plant will need more care.
A box hedge prefers a location that is sheltered from wind. All types of box dislike growing in shade, but too much direct sun is also a problem, and the two extremes bring risks of scorching and fungal diseases. Box doesn’t like to be too damp, so it is best to plant it into sandy or loamy soil. The best time to plant or relocate a box hedge is between October and the start of May.
Box hedges look their best when they grow thick and solid-looking – especially if you want them for screening or topiary. To achieve good density you need to trim your box properly, regularly and with care. The right tool makes all the difference, as working with something precise, easy-to-use and reliably sharp ensures clean pruning and no unnecessary stress on the plant. STIHL has a wide selection of hedge trimmers, from manual to cordless, which make the perfect accessory whether you want your box hedge trimmed with formal elegance or with a little more artistry.
Working with powerful tools is fun and means you can extend your abilities, which is great as long as you are relying on effective and safe protective clothing while using them. Always wear your personal protective equipment when working with your hedge trimmer. This includes safety gloves, safety glasses, ear protection and more. Please see the operating instructions for your product for further details.
Before you use your chainsaw for the first time, you should familiarise yourself thoroughly with the tool and ensure it is in flawless condition before each use. On request, your STIHL dealer will be happy to prepare your tool for its first use, and will also advise you on models and sizes of protective clothing that you can try at your leisure. Please remember that personal protective equipment is no substitute for safe working techniques.
It’s no surprise that box hedges are such a popular choice as a garden border hedge; after all, with the right care it grows so dense that privacy is assured. Proper box hedge care techniques go hand-in-hand with having the right tool for the job. We recommend using a cordless hedge trimmer such as the STIHL HSA 56 cordless hedge trimmer. Whatever tool you use, make sure that the blades are sharp so you can guarantee a clean and effective cut and avoid crushing parts of the plant.
How to plant a box hedge border from scratch:
STIHL pro tip: If you “inherit” an old, neglected box hedge, don’t be afraid to be ruthless: you can cut the hedge back hard to rejuvenate it and get it back into shape. Cut the individual plants down to about 1 metre in height and trim outward growth so stems are a maximum of 10 centimetres long. This kind of trimming is best done in February and March, and should be followed with an appropriate fertiliser to boost the plants’ recovery. Healthy box cuttings can go in your compost bin.
With a little extra flair in your trimming, you can not only maintain your box plants but also make them into eye-catching balls, pyramids or spiral shapes. This work is more intricate than most hedge trimming jobs, so we recommend that you start out using manual shears, though experienced box gardeners can certainly produce top-class results with an electric hedge trimmer.
In general, avoid trimming box hedges and plants if it is raining or if heavy rain is expected. Very sunny days are also not good though, as both kinds of weather can damage freshly cut box: rain may rot the cut surfaces, while the sun can scorch newly exposed tender leaves. It is best to wait for an overcast day if you need to give your box a proper trim.
In terms of cutting technique, whether you are using a cordless or manual hedge trimmer you should always cut at a slight angle. You should also ensure that the blades of your trimmer are sharp, to prevent the plant from being crushed or damaged, leaving it open to infection.
You should fertilise your box plants three days after trimming. A suitable feed at this point helps ensure a quick recovery and also makes your hedge more resilient, as a box plant with strong growth and strong roots is also better protected against possible pests. Another important step for protection against pests is proper watering – doing the wrong thing here will render your box susceptible to fungal infections. You should never water from above so the leaves get wet; instead, always water the soil at the roots. If possible, use collected water from a water butt. Freshly planted box need more water in their first two weeks than established plants, though the exact amount needed is dependent on the soil, location, and the type of plant.
STIHL pro tip: A box with well-established roots – which can be identified by steady growth and a deep green colour – should only be watered on hot days and in dry locations. Box are hardy native plants that generally take care of their own water needs, using long roots to find moisture underground. The best way to tell if your boxwood hedge needs watering is to check the soil under the plant with your finger: if it is moist at a depth of 2 to 7 centimetres, everything is fine.
A box plant in a pot will broadly need the same care as one planted in the ground, apart from in terms of the amount of water it needs: because potted boxwood plants cannot supply themselves with water they need regular careful watering, though there should always be a drainage hole in the bottom of the pot to prevent waterlogging. Ideally, you should place the pot in a saucer filled with ceramic shards to prevent mud from accumulating in the drainage hole. In pots as well, always water boxwood at the root as described above. If your potted box plant does fall victim to a fungal infection, this is relatively easy to treat: simply wrap it in a clear plastic bag and place it in intense, direct sunlight during the summer. The fungus should be dead after a day in the heat.
Box plants are hardy and do not require any particular care during the winter. That said, do remember to water occasionally on frost-free days and to regularly clear away any snow that accumulates on them. Potted box requires a little more care in the cold, as its roots are vulnerable from all sides. You can counter that by wrapping the container in a thick layer of bubble wrap; this insulates the roots of your box plant against winter temperatures.
A box hedge is certainly a thing of beauty, but also quite susceptible to diseases and pests, with some problems necessitating radical measures. Here is an overview of the most common box diseases and pests, with some advice about how to treat them.
The box tree moth is originally from Asia, and it is a voracious pest that can quickly ruin your plants if not addressed. Partially eaten leaves are a tell-tale symptom of an infestation – and the need for urgent action. The moment you spot a caterpillar on your box hedge plants remove it; search carefully and remove any others. If you are dealing with an advanced infestation, the best strategy is to completely cut out affected areas – it feels extreme, but prolonged infestation is sure to be ruinous. Burn the removed branches or dispose of them with your household waste.
Brown, sparse foliage and dark stripes on your box plant are indicators that it is infected with the cylindrocladium buxicola fungus or box hedge blight – one of the most common pathogens that affects boxwood plants. If you catch the disease at an early stage, you can treat plants with a specialist remedy from a DIY store or add some calcified seaweed to strengthen the plant. Sometimes this is enough to eliminate the fungus and save your box hedge. However, this fungus is very aggressive, and it may be impossible to rescue a box that has been severely impacted already. In that case, you will need to remove the entire infected plant as well as any leaves that have fallen from it, disposing of all blight-affected parts, preferably by burning or industrial composting.
Older box plants in particular are more likely to suffer from boxwood rust. Caused by a fungus named puccinia buxi, the condition manifests as small, brownish spots on the tops and bottoms of boxwood leaves. Boxwood rust is extremely easy to treat: all you need to do is cut back any affected stems, and healthy new shoots will grow in their place. You should disinfect your hedge trimmer after use to prevent spreading the fungus.