Picture the scene: grand country house, two acres of pristine formal gardens with traditional topiary. Nicky Fraser and her husband, Johnny, have been asked to clip a particularly fine statue complete with yew plinth. Johnny is at the top of the ladder, while Nicky stands on the ground, trimming the plinth. The pomp of her surroundings has agitated the rebel within. She clips a large circle into the plinth, followed by a capital A inside it: the symbol of anarchy.

After much giggling and taking photos she quickly shears it off before the owner comes home. No harm done. But all the excitement alerts one of the groundsmen. He thought he’d score a few brownie points by telling the boss. Nicky didn’t expect to be asked back. But she was, and the owner wasn’t upset. “I think she rather liked it – something naughty but nice,” says Nicky. And in the process, Nicky realised that she wanted to write something that others would see.

For years, Nicky had driven past an immaculate conifer hedge in a front garden near her home in Shropshire. She had been eyeing it up for some time, and after she sent her diplomatic husband to knock on the door, the owners invited her in for tea and cake. They were members of the parish council, and following Johnny’s visit they had been thinking along the lines of “the name of our house in small letters”. Nicky had other ideas: “If I’m doing it for free, I decide what I write.” A compromise was struck: they agreed to let her clip what she wanted into the front of the hedge, providing she clipped the name of their house on the other side.

topiary you are here

A traffic-stopper… Photograph: Danny Beath

The hedge was at the entrance to the village, so all the traffic had to slow down as it approached. Nicky clipped “You are here” in gigantic letters. Bus drivers slowed down to look, every face inside staring out of the window; lorry drivers beeped their horns, and passersby stopped for a chat. “It was heartwarming stuff,” says Nicky.

The couple loved it, and word got round. Since then, Nicky and Johnny’s company, Knives Out, has taken off. “I like to shock people, snap them out of autopilot,” Nicky says. She doesn’t just do green graffiti: she clipped a long, cloud-pruned hedge overlooked by a fox, and carved a capital D into perfect box cones, transforming a symbol of grandeur into a dunce’s hat.

In her own garden, Nicky likes to surprise the postman with things she couldn’t get away with in other people’s gardens. “He loved my lost souls,” she says, referring to the set of skull-shaped box balls growing haphazardly from an otherwise unremarkable flowerbed.

topiary lost souls

The lost souls. Photograph: Danny Beath

She eyes a hedge in the way a sculptor eyes a block of stone: she can see the message trapped inside, waiting to be liberated. So how does she do it? “I couldn’t show you how I do it, it just happens. All I know is that I can do it with my eyes shut – I’ve tried.” And like a genie let loose from a bottle, the result is usually mischievous.

Topiary tips

Tools Forget garden shears; you need a pair of specialist topiary snips (try niwaki.com). They’re razor sharp, and the blades are only 5cm long, perfect for writing and sculpting. A simple pair cost £30.

How to write The letters must protrude, so the trick is to clip the rest of the hedge around what you want to stand out. Make sure the hedge has been clipped regularly, so you have a flat canvas with no gaps: when it’s next due for a trim, give it a go. The letters need to protrude only a few centimetres to show up.

Suitable hedges Any dense, small-leaved evergreen can be used, but Nicky favours yew, box, lonicera and privet; the latter grows quickly, so any mistakes will soon grow out.

What to sculpt It doesn’t have to be elaborate; a simple cube would work well. And carving out a topiary skull is easier than it sounds – begin with a ready-made ball shape and simply trim two eyes and a mouth. If you start trimming now you’ll have something in time for Halloween. Children will love putting their hands inside the eye sockets.

Maintenance Box or yew need trimming only once a year, in early or late summer; the faster-growing leyland cypress or privet need doing in early summer and again in late summer. Always use a sharp blade, and every now and then wet the blades as you trim.

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Charlie Dimmock

Gardener at BBC Gardeners World
Charlotte Elouise "Charlie" Dimmock (born 10 August 1966) is an English gardening expert and TV presenter. She was one of the team on Ground Force, a BBC gardening makeover programme.