Thinking outside the box: a year in the life of a box hedge

We’re renowned for our topiary techniques at Abbotswood, and our team of master craftsmen are responsible for pruning and clipping some of Cambridge’s most beautiful hedges and free form box sculptures. Here we share our tricks and tips on box – and the dreaded blight – so you can box clever in your own garden…

July & August

At this time of year, as the new growth is beginning to firm up, we like to save some of our clippings as semi-ripe cuttings for propagation. We’ll cut lengths between 10 and 20 cm long, strip off the bottom leaves and pop them into pots of compost (one pot will take around five cuttings), water them and leave them in a cold frame to root undisturbed. Roots can show after eight weeks in a heated propagator, but outside they’ll take up to eight months. Grow them on, pinching out the tips regularly and plant out the following autumn.

September

Our box gets its final hair cut of the year this month. In damp years, we’ve seen growth of up to 18cm between the final autumn trim and the June cut – and although it’s tempting to cut box earlier in the season, especially as the weight of the new growth can splay out and create gaps, it’s better to wait. Any earlier and the soft, new growth is vulnerable to leaf scorch from sun and drying winds; any later and it can be damaged by frost. Once the damage has set in, the plants are more susceptible to diseases such as box blight too. 

October & November

We like to give our box a mulch at this time of year, and plant new specimens. Tolerant of a wide range of soil types, provided there’s good drainage, box is happy in deep shade too, so is a good choice for under planting below tall trees. If you’ve not taken your own cuttings, now’s a good time to order in bare root plants, which can be planted at a spade’s depth into a hole three times the width of the root ball. The most common cultivar is Buxus sempervirens, which tends to be quite vigorous (so is not the best choice for regular trimming) but there’s also B. ‘Suffruticosa’ and Buxus microphylla, both compact cultivars with smaller leaves that makes excellent topiary, and Buxus microphylla ‘Faulkner’, which is very hardy, has glossy, emerald green foliage and is resistant to box blight (cylindrocladium buxicolabox) and volutella buxi. Trimmed into shape within one season, bare root box can be a fraction of the cost of container grown specimens.

December, January & February

Evergreen balls and sculptures really come into their own in winter, and after their final prune they have a beautiful crisp outline, which can look stunning with a dusting of frost or snow. As box topiary is expensive to buy – the price reflects the slow growth of box and the many years needed to trim into shape – we’d recommend adding one to your Christmas wish list!

March

The start of spring signals the beginning of the feeding season for our hungry box. We’ll apply a bonemeal or ‘Top Box’ feed that’s not too rich in nitrogen – a diluted seaweed feed works well too – and this is especially important if your box is in a container. Signs that your box is short on nutrients include a slow down in growth, browning leaves and yellow tips, but a good feed can remedy this in a few weeks.

April & May

Forget Springwatch, April is pest watch for our skilled topiarists! We’ll monitor all our hedges for diseases and particularly for box blight, which is caused by two fungi (Cylindrocladium buxicola and Pseudonectria buxi). Blight causes the leaves to brown and fall off and bare patches to form, and it’s worse in wet, warm conditions. For us, prevention is better than a cure so we’ll always clean tools between plants in the same garden and extract any cutting debris using a blower, as decaying material provides a host for pathogens. 

June

The traditional day to start clipping box is Derby Day in early June when the new growth has lost its flaccid, lettuce like quality. For us, pruning topiary has an immersive quality akin to woodcarving and can be very absorbing! Box in particular is perfect for topiary as it is quite forgiving and the plants have multiple layers of foliage, which means you can trim quite hard to perfect your shape. We use hand shears for best results and we’ll cut sections quite swiftly, sometimes as much as 50 meters of hedging a day, while a small 50cm box ball may take as little as 15 minutes. You can take your time, of course, and it pays to regularly stand back to ensure you’re getting the desired shape. At one level, you can use box to create perfect geometric shapes, which give order and structure to the garden but on the flipside, free form designs and organic styles allow you to explore the fantastic character of this plant and achieve something quite unique.