I have always thought of this garden as a new garden: showing people round was like showing off the accomplishments of a precocious toddler. “Look!” I would cry. “These yews have only been in two years and see how they flourish.” Slowly it has dawned on me, however, that my chubby-fingered baby has grown into a teenager: sometimes petulant, often wilful, but always lively and extraordinarily beautiful. The history of any garden will also, to an extent, be the autobiography of the gardener and, while I hope that this will not be my last garden, it will always be my first love. Of course, so much that seems important to the gardener can appear awfully dull to the outsider – rather like imposing a slideshow of baby pictures on a bachelor uncle. I will try not to be too boring.

Fifteen years ago we left the characterful sprawl of southeast London and bought a farmyard in Northamptonshire. It consisted of an enclosing square of cattle sheds, a vast central barn and a lot of rubbly concrete. We first visited it on a drizzly Saturday morning and saw potential. We knocked down the barn and built a house – which was completed a couple of weeks before our younger son was born in our bedroom (impending childbirth is an excellent way of ensuring that builders stick to schedules). There then followed a slight hiatus when we lived in a sea of mud. Even the shortest foray resulted in dirty footprints and grubby children and the only access to the house was via a slippery scaffolding plank. The day that the postman took a tumble was the day it was decided that we ought to think about the garden.

When describing the birth and development of other gardens, those I have designed for clients, there is an obvious path. The site is surveyed, the client’s needs are considered, plans are drawn up, contractors appointed, nurseries contacted, compost spread and everybody lives happily ever after. In my own garden it was less organised. Stage one was just clearing up: concrete was broken up and shifted, the sheep dip was filled in, a silage heap was cleared of rusty washing machines and a smelly old caravan was incinerated spectacularly.

After that we were left with a tobacco-coloured mess that, while free of lumps, was also totally devoid of any goodness, so stage two was to get hold of some topsoil. Dumper trucks roared about, chaps with diggers dug, I ran from one place to another brandishing rakes. About halfway through the process it dawned on me that we did not have enough soil to do the job (and no money to buy any more), so the layers got thinner and thinner. There are still places where all planting has to be done with a big steel spike. But within a few weeks the first wavering green of a lawn was showing through the mud. Finally, the years of farmyard and building site were over and a new incarnation as garden had begun.

There have been many lessons learnt along the way; it is, after all, intended as a place of experiment and evolution. I must confess that I sometimes buy plants on impulse without any idea where they will go – many have, as a result, remained behind a shed until they passed away from neglect. The pond is still incomplete, one part of the garden has lousy drainage and the first pergola I built fell over. There have, of course, been triumphs as well. My elder son and I built a new pergola from galvanised-steel scaffolding poles, an arrangement that allows much more light to reach the ground, which is an ever-changing sea of self-sown plants. A load of leftover soil from another job was used to create an instant raised path that slithers its way along one side of the garden. One side is planted with a dragon-backed yew hedge and the other with bronzey Anemanthele lessoniana. This is now the Grass Snake (because it is both grassy and snake-shaped) and gives a fabulous view across the ever-expanding borders.

But above all, this is a garden about plants; everything else takes second place. We began, as most gardeners do, by planting whatever was easily available: a mixture of things that were donated by relatives, scrounged from friends and, in my case, left over from various jobs. This strange amalgam of plants began to form into borders – it would sound good to say that all of those plants were the perfect choices placed in perfect positions, there to remain and grow tall and strong. However, to do so would be a lie as, without exception, I have dug up or lost every one of those original plants. I have always regarded plants as replaceable – they are not, after all, kittens – and the planting scheme is constantly changing. The general feeling now is one of lively chaos, with lots of enthusiastic plants tumbling over each other to create a kind of pandemonium. Paths become impassable, terraces are invaded and benches colonised. The area that suffers most is the lawn: I have always held the view that a large flower bed is much less work than the repetitive tedium of lawn-mowing, and as a result it tends to get a little smaller as year by year the borders quietly purloin another few inches of grass.

A happy garden will always be a work in progress. Things should always be ebbing and flowing; plants come, plants grow; insects breeze about; birds arrive, fledge and leave. It is a busy and thriving metropolis without the inherent transport problems. Forget Samuel Johnson’s famous remark about London: surely it is more apt that the man who is tired of gardening must be tired of life?

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