“It’s like the Lost Gardens of Heligan,” I said, looking at the broken-backed and sagging greenhouse, the shattered hut, the row of abandoned, stone-built cold frames, the overgrown woodland walk where, some 80ft above the rampant rhododendron, two huge and majestic monkey puzzles seemed to be distancing themselves from the unseemly riot of unfettered plantlife. Should we buy it? Our son, Andrew, was a squirming 18-month-old. Our daughter, Isabella, was just-born. We were both working, commuting between Derbyshire and London. Did we really need to take on a wilderness like this? The house that the garden belonged to was a tiny place shaped like a castle, a flight of high Victorian Gothic fancy, admittedly, but with Victorian Gothic heating (or lack of it). It would need gutting, redecorating, and in some parts rebuilding.

And so, of course, we didn’t hesitate. I write books for a living – glamorous comedies – and this tiny, turreted house in the midst of its wilderness of garden seemed to me to ooze glamour. Rather more boho chic than the Versace sort, admittedly, but I’ve never been a sequins-and-stilettos type of girl. The Lost Gardens of Heligan became the Lost Gardens of Holden. And slowly, gradually, they have become found.

One hundred and fifty years ago, our house was the gardener’s lodge, and our gardens the kitchen gardens supplying the still-inhabited nearby Hall (which these days gets its vegetables from Sainsbury’s). All the Hall gardens were reputedly designed by that high priest of Victorian horticulture, Joseph Paxton, moonlighting from his job as head gardener at Chatsworth, just over the hill. We knew little about Paxton, not even that he built the Crystal Palace, when we first came to live here. And personally, I knew practically nothing about gardening. The entire time we lived in London – 14 years in a flat in St Pancras – I didn’t know my artichoke from my elbow, nor did I much care about finding out. Yes, we had window boxes, maintained by my husband, but even watering those was an effort.

Things couldn’t be more different now. For one thing, my husband is a passionate gardener and in his element here. Soon after moving in I found that if I wanted to talk to him at all I had to go outside, even when it was raining. At first this meant standing next to him under an umbrella, me wittering as he patiently weeded away. But after a while I found myself bending over and tugging the odd dock out as well. Now I can’t walk past a weed without uprooting it. There is nothing quite as satisfying as removing the deep yellow root of a millennial nettle that has lain undisturbed since the days of Queen Victoria. The Constant Gardener is, as my husband says, the Constant Weeder. We waged merciless war on mare’s tail, and I was outraged whenever I received, in the junk mail, children’s mail-order catalogues picturing some ruby-lipped babe blowing a dandelion clock. Those ghastly seeds going everywhere!

Soon we would spend all our available time outside, wandering past the borders after the children were in bed. At first, I would just listen to Jon’s plans for the restoration: rebuilding the greenhouse; creating a new vegetable garden; overhauling the rhodo-rampant woodland, and so on. But then I found, rather to my surprise, that I had ideas as well. How about extending that path up to the wall and putting a seat under that pretty magnolia? And what about a box garden next to the main front lawn?

Even now, four years after we first came here, we rarely make a tour of our three acres without having had some new thoughts. These are invariably taken on the chin by our wonderful gardeners, who cheerfully tackle any task, from making new paths to making new war on the nettles. Our garden was originally intended as grand and ornamental. Our decorative little house, a castellated jewel amid ordered vegetable and flowerbeds and glasshouses of exotic fruit, was obviously the focal point for walks by the great folks from the Hall, one of whom was an uncle of Charles Darwin. The great biologist even came here and was most interested in the wild boar, whose descendants are still farmed across the valley.

Gardening here was gardening in the grand style. We have made fascinating discoveries while pulling up, cutting down and digging over. A great, thick, Victorian bell jar. Enormous bootscrapers of the portable sort that used to be plunged into the vegetable beds on muddy days. Bottles – alcoholic, medicinal (possibly the one leading to the other) – of all kinds. Ancient Dinky Toys. Meanwhile, the great 19th-century cast-iron pipes which once warmed the greenhouse, and the fact that the cold frames have ancient electrical connections, provoke the sobering realisation that the marrows, grapes and figs once grown here enjoyed modern amenities at a time when most human beings in the area – including the gardener in his house – were still getting by on candles and firewood.

We are indebted to our predecessors here, who uncovered so many of the old beds and pathways. Yet there has been – and remains – an enormous amount of grunt work in continuing to restore the garden; a lot of digging, raking and loading of wheelbarrows. But we’ve tried to bring back some of the Victorian flamboyance, too; the fun and glamour of it all. The fruit cage we built has Gothic finials. The new vegetable beds are surrounded with box, framed with cobbled paths, and have a large urn in the middle. Another urn, fabulously large and gloomy, glows reddish from between a group of larches in the woodland walk.

We add touches from other places as well. Our long-time love of the South of France finds expression in the lush lavender fringes to our lawns and the jardin lapidère of decorative, mock-Classical stone fragments at the back of the patio. Our work is bearing fruit, quite literally. There were some very old plants in the ruined greenhouse – one reason why we decided not to knock the old structure down, but instead rebuild it, strut by strut, on site. As a result, the huge, old muscat grapevine is enjoying its first summer for many decades under proper glass. The ancient fig, also in the greenhouse (it’s like The Song of Solomon in there), is thriving too, as is the row of new apple trees behind the fruit cage. I have developed a passion for poppies and peonies and a whole new love of lupins.

The joy and fascination of vegetable growing – the heaven of having your own rocket! – has been a particular inspiration. My new novel, Filthy Rich (mostly written in a summer house in the garden), is a romantic comedy set on an allotment. A group of widely differing characters, including a WAG with a Chanel spade, and Kensington Incomes with a Cath Kidston shed, find happiness through horticulture. Some entirely unexpectedly. Almost as unexpectedly as me.

Filthy Rich is published in paperback on August 21 by Headline Review, and is available from BooksFirst priced £6.64 (RRP £6.99), free p&p on 0870 1608080; timesonline.co.uk/booksfirst

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