It was a friend hissing “She’ll never do it” that finally got my dander up. “It” referred to a long-overdue overhaul of my little back garden, which gives onto one of the lush communal gardens in Notting Hill, west London. I call this private green idyll “the gardeners’ garden”, as my neighbours all seem to be persons of horticultural or design distinction.

They include Henrietta Courtauld, a talented garden designer; Peter Clay, the founder/owner of the gardening website Crocus; the wall-coverings baronet Peter Osborne; and the architect John Pawson and his designer wife, Catherine . All have gardens of heartbreaking beauty that somehow mirror their individual personalities and passions.

And ours? Well, let’s just say it was a small, dark, scrubby patch with a few unruly shrubs that, to my certain knowledge, had never been trod in our 15 years of residence by either my husband or my three children - except to retrieve a stray football, that is.

Neighbours would wander past, their gaze politely averted from the eyesore, and tell me they did so admire my wild-garden approach or commend me for my lack of self-consciousness about the two dead Flymos, the rusting trampoline and the other detritus that adorned the outside areas.

So, I took the hint and got in three top and trendy designers, who each drew up plans. Still I didn’t stir, mainly because the cheapest design, excluding labour and materials, was £5,000. “Can you do it for £2,500?” I asked my friend Lila Das Gupta, the allotment ninja and one-woman whirlwind. “Yes,” she said, and we were on.

So it was that, in one day, she put things mostly to rights. (I’ll come to that weasely “mostly” in a minute). Once Lila was on board, that was it. It was a blur of activity. I remember getting out my credit card and paying for a truckload of gravel and a thumping big order from Crocus. Peter generously gave us some items labour-free and at wholesale prices, but it still came in over budget, at more than £3,000, plus the gravel.

Soon, the day that Peter, Lila and I had put in the diary arrived. It was Makeover Day. I woke up with a start at 6am. Where was the gravel? It should have been delivered the day before. This was one of the few things I was in charge of, and I’d forgotten all about it.

At 7am, I called the builders’ merchants and knew the gods were smiling on us. Not only was it a beautiful day, not only was my garden going to be glorious, but, two tons of shingle and a roll of weed-suppressing membrane were on the way, as was the Crocus delivery.

Peter brought Kent, a colleague from Crocus, to help, so Lila and I went off to the DIY store in search of planters and containers, paint for the peeling garden furniture, Scilla peruviana, euphorbia, a daisy grubber and other sundries.

I should have realised that Lila intended to make a splash when, as we raced around, she grabbed a large tin of Cuprinol. Nothing strange about that. But it was purple. I held it up. “Surely we want a clear varnish?” I said, in a faltering voice.

I live on a communal garden. When Peter painted his rear elevation blue, he received 46 letters of complaint that it was “the wrong shade” of blue for the garden. Not only that, I live with a man of upper-class mien who doesn’t buy his own furniture and doesn’t buy in his taste, either. I tried to explain this to Lila as we stood at the checkout, but she gave me a fierce look and firmly replaced it in the trolley.

I began to realise that resistance was futile, and as I paid for a tin of equally purple paint, for the outside extension wall, in Farrow & Ball’s showroom on the Fulham Road, I began to sense that where Lila went, fireworks might well follow.

In the next seven hours, we worked harder than I believed possible. The ground was levelled and prepared for the new plants: two huge tree ferns that wouldn’t look out of place in Jurassic Park; four 30-year-old Sicilian olive trees, splendidly bushy and sturdy; Christmas box; ‘Madame Alfred Carrière’ roses and eight lavish white foxgloves. Dead ivy was taken off the trellis and wire netting from around the railings. By me, no less.

As I wondered a little about how the tree ferns would look (my taste veers towards the sweet, tumbled, cabbage-rose style of the English cottage garden), and Lila started painting our extension purple, Catherine Pawson came out from her minimalist masterpiece of a house – where the only colour allowed is white – and a look I’ve come to know well came over her face.

“It’s a new Farrow & Ball paint colour,” I started bleating. “It’s called Pelt.” Catherine’s nose twitched ever so slightly. “Ah, in case I want to use it,” she murmured. “Why are you apolo-gising?” Lila demanded.

Kent dug and dug, and some of the olives and the ferns were put in. Then we manhandled the rest of the olive trees to the roof terrace. It was all beginning to come together. The gravel went down, the furniture in. The brazier was lit, the champagne popped. We’d done it. It looked smart, in a groovy, 1960s way. We posed against the purple wall and toasted each other.

Then my husband came home. “Apart from the fact that the olive trees on the terrace block off the view and the olive trees in the garden block the light, and the fact that the ferns are hideous and totally out of place in the communal garden, and that you’ve paintedmyteak garden furniture from Aunt Pam purple, and you’ve painted the house purplewithout consulting me first, and the gravel would look naff in a Surbiton semi, I like it very much,” he said.

A total success, in other words. I am very happy with it, which is what matters. And Lila did a fabulous, low-maintenance, high-impact job given the budget, the space available and her not very green-fingered clients. In time, the makeover might even grow on the master of the house, too.

My neighbours have yet to comment, but no angry letters about the purple paint so far.

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