Two minutes’ walk from Baker Street Tube station, yet light years from London’s daily grind, is the extraordinary HQ of Lucille Lewin, founder of the Whistles fashion chain, style saviour of Liberty and all-round fashion-world éminence grise. Chiltern Street Studio, her converted Victorian school tucked behind a gated Gothic archway, is an oasis of calm that is architecturally a reimagined step back into a gentler past, professionally a design hub fast-tracking future trends, and also a commercial venue for hire, for anything from product launches to film shoots and private functions.

The stone-flagged courtyard has served as a hothouse of tropical blooms for a perfume launch by Calvin Klein, overflowed with lilies and champagne for Moët & Chandon, and been magically showered with snow in scorching summertime by a production company. Now it has a permanent garden all of its own, reflecting, respecting and reinforcing the building’s identity under Lewin’s impeccable art direction by using two talented up-and-coming gardeners, Adam Woolcott and Jon Smith. The pair were earmarked for this project even before they won three successive gold medals at the RHS Chelsea Flower Show – that’s trend prediction for you. Yes, there was an awful lot of prep and consultation, but the miracle you won’t believe from the photographs is that this garden was crafted from scratch in just seven days.

Since selling the Whistles chain seven years ago, Lewin has been free to pursue other interests: sympathetically restoring and extending this school building – in association with architect Seth Stein – to carve eight luxury flats from assorted former classrooms has been one of them. Networking, consultancy and launching new talent via seasonal trade shows have made her the uncrowned queen of contemporary fashion. She’s also chair of Vintage Academe, which celebrates, conserves and sells the high couture of yesteryear via the internet.

Her time is now her own, to use at will, and much of her effort goes on her homes and gardens. An eco-friendly house designed by Stein in Lewin’s native South Africa merges effortlessly into the wild fynbos landscape; and the rooftop of her London home is a container-grown collation of herbs, fruit and vegetables, as much a visual feast as a comestible one.

The studio garden is something else again, another triumph. Lewin’s brief to Woolcott and Smith was for a garden that would look great through every season and work as well by night as day. A tall order indeed, especially as surrounding high walls demanded shade-friendly planting. The back-story was of an imaginary Victorian benefactor whose Grand Tour treasures, mixed with everyday gardening paraphernalia, would become a living cabinet of curiosities, both overrun and pulled together by lush planting. Architectural salvage yards and antique shops were scavenged, and mature ivies were ordered from Italy to be painstakingly untwined and retrained.

Woolcott and Smith clearly know their business inside out, as does their landscaper, Cormac Conway. His brickwork is so beautifully understated, it looks like it’s been in the garden for ever; raised beds had to be installed because the soil beneath the York-stone slabs consisted of hard core, London clay, gas pipes, water mains and electricity cables – not a conducive planting mix. An irrigation system keeps maintenance to a minimum, and artfully concealed lighting brightens the nights.

The mostly evergreen mix comes with built-in surprises. Deciduous male ferns unfurl with dynamic tension; winter box will soon scent the air with a sharp honeysuckle zing; snowdrops, bluebells and lilies appear in season; and the curiously button-leaved climber Muehlenbeckia complexa brings unexpected autumn fragrance. Teasels, foxgloves and teardrop pearl flowers on arching Solomon’s-seal stems add height, grace and a touch of the wild, while ground-cover plants, such as baby’s tears and snake grass, colonise nooks and crannies incorporated for that very purpose.

Best of all, this couture creation was tailored to a prêt-à-porter budget.

www.chilternstreetstudio.com; www.woolcottand smith.com; www.conwaylandscapes.com

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