Matthew Williamson describes his design aesthetic as ‘rustic decadence’, which may sound slightly contradictory, but this neatly encapsulates his love of nature and glam Bohemia. It’s a style he’s been playing with ever since he decorated his childhood bedroom in Manchester in outré shades of silver and lilac, and consolidated when he burst onto the fashion scene with his riotously colourful debut collection more than two decades ago.

In his current day job as interior designer, he has been able to give full expression to that artistic passion, creating fabulous spaces filled with bold colour, intricate prints and exotic treasures, designed to evoke – as he attests – ‘joy and optimism’

Williamson, 48, is at the forefront of a new wave of designers and decorators, reimagining traditional British style with an emphasis on sustainability and craftsmanship. ‘I’m not one for trends, whether in fashion or interiors; I’m guided by my gut and the design DNA I have stayed close to all of my career. But I do think people are buying pieces with more of a conscience now, seeking out designs that are well-made and built to last so that they are sustainable for years to come,’ he says. ‘Florals are a key motif for me and I have some chintz-style fabrics that have been bestsellers. But all of these will have a modern, unique twist, whether in colour or an unexpected detail. I will never do a literal or traditional floral or pattern as that’s not what excites me creatively.’

For Williamson, who recently launched his first tableware collection with home décor brand Les-Ottomans and has created limited-edition Christmas bouquets with flower delivery company Bloom & Wild, the shift from fashion into lifestyle was inevitable. ‘It’s always been an intrinsic part of my design identity – from my early collaborations with brands such as Habitat to the interiors of my stores. I see it as a natural progression,’ he explains.

It was also extremely low key, perhaps surprisingly so, given his reputation as one of Britain’s best-known designers with an army of loyal celebrity fans, including Sienna Miller, Gwyneth Paltrow, Kate Moss and Jade Jagger, who wore his lavishly embroidered, boho-chic party dresses like badges of honour. He celebrated 18 years as a fashion designer in 2015 with what turned out to be his last show at London Fashion Week. There was no fuss or major announcement; he simply closed his stores, including his flagship Mayfair boutique, and revealed he was branching into e-commerce, focusing on a more personalised customer service by cutting out the middleman.

‘It was a natural pivot of the business, rather than a dramatic shift,’ he insists. ‘We listened to both our customers and my own creative impulses. It all pointed in the direction of lifestyle.’ As he told Vogue at the time: ‘The jigsaw pieces are finally coming together because I believe the woman that wants that dress also wants a velvet marbled butterfly armchair.’

A consummate collaborator, Williamson started putting those jigsaw pieces in place as early as 2003, when he joined forces with The Rug Company to produce a range of rugs using prints from his ready-to-wear collections. He then popped prints onto Coca-Cola’s iconic glass bottles and, in 2011, designed wallpaper for Habitat. Wallpapers and fabrics for Osborne & Little followed, as well as his Butterfly Home collection for high-street giant Debenhams.

He’s since designed everything from gardens to bridal suites, and recent commissions include a bespoke suite of rooms at the exclusive Belmond La Residencia hotel in Mallorca, featuring hand-painted vintage furniture, marabou feather-trimmed lamps and luscious bird and butterfly prints.

It’s no coincidence that the designer now calls Mallorca home; he moved to the idyllic artists’ retreat of Deià on the west coast four years ago, shortly after his daughter Skye was born, and he admits the move ‘marked a change in pace, which I have enjoyed. I find myself very stimulated creatively here,’ he says. ‘I love walks with my daughter and dog, whether on Hampstead Heath (near his north-London flat) or round the coastal paths in Deià.’

For both properties, he applies his interior design philosophy: ‘To make a house feel like a home’. He says, ‘My homes in London and Spain are both organised bohemia, I would say! My flat in Belsize Park has great scale and bones; it might look like it’s all been thrown together but, actually, everything is in its place.’

Williamson’s extensive travels to such far-flung destinations as India, Costa Rica and Mexico have long informed his designs, providing inspiration as well as a bright contrast to his native Manchester. India in particular has provided endless inspiration: ‘I’ve been more than 40 times and I’m forever intrigued by the colours, vibrancy, diversity and craftsmanship.’

‘I’m fascinated by the world around me – the colour first and foremost,’ he continues. ‘In Spain, I’ve been referencing the lush flora, citrus fruits and playful songbirds.’ One recurring motif is the peacock: ‘I’m drawn to the symmetrical plumes, ornate detail and sumptuous colourings. Peacocks featured back in my first show, and we made one of our most popular dresses with a peacock print.’

Williamson’s status as interiors guru was sealed this year with his appearance as guest judge on the BBC’s Interior Design Masters, presented by his friends Fearne Cotton and Michelle Ogundehin. ‘I loved meeting the contestants and seeing their style develop significantly by the grand final,’ he enthuses. His next big project, he reveals, is to bring together his interiors portfolio in a new online retail space. Would he consider a return to fashion? ‘Never say never, but I’m happy and fulfilled with my work today, which as a designer is all you could ever want.’

matthewwilliamson.com