Strumming my box-fresh ukulele, I can’t stop grinning. I’m an hour into my first workshop, and I’ve just about got the hang of a Buddy Holly song. Buoyed, I venture to join the rest of the group in singing the chorus. Immediately, I lose my grip of chords and rhythm, but I quickly recover and join back in, satisfaction barely dented. Having slogged through recorder and piano lessons, and after trying but failing to teach myself guitar as a teenager, this speedy success at making music is a new experience for me, and it feels great. I’m beginning to understand the unlikely popularity of these dinky, four-stringed micro-guitars among musicians, trendy urban types and schoolchildren alike.

Inextricably connected in many minds with acts such as George Formby and Tiny Tim, the ukulele has enjoyed something of a renaissance in recent years, earning a credibility among musicians and a popularity with amateurs it had lacked for decades. It was invented in the 19th century by Portuguese sailors who wanted a portable version of the guitar to take on long sea journeys. Early versions were taken to Hawaii; natives gave them their name, which translates as “jumping flea”, a reference to the speedy fingers of an expert player. Although used by vaudeville acts during the early 20th century, and much loved by George Harrison, the ukulele was considered an anachronistic museum piece, despite the efforts of the Ukulele Orchestra of Great Britain, who have performed virtuoso versions of songs as diverse as David Bowie’s Life on Mars? and Ms Dynamite’s Dy-Na-Mi-Tee, at venues including Festival Hall and Glastonbury, since they formed in 1985.

Yet today, the instruments are flying off shelves at guitar shops countrywide. A specialist store, Duke of Uke, in Spitalfields, east London, has been thriving for the past 18 months and counts Tracey Emin and Pete Doherty among its customers. Britons spent at least £300,000 on ukuleles in the past year, twice what they spent four years ago, according to the Music Industries Association. Trade has been so hot this summer that manufacturers have been unable to keep up with demand, forcing customers to join waiting lists. Graeme Ross, of the Guitar, Amp and Keyboard Centre in Brighton, says: “We’ve gone from selling one or two a month to one or two a day, and we’re increasingly being asked for the better-quality ukes, with good tuners and pickups, that few manufacturers even made a couple of years ago. It seems people get interested by playing the cheap ones, then upgrade.”

Learner groups meet in pubs across the country, and amateur evangelists include Warren Buffett, one of the world’s wealthiest men, who played one on stage at his annual shareholders’ meeting this summer, and Tom Hodgkinson, the bestselling author of How to Be Idle. Ukes were strummed at Glastonbury’s camp sites, and the End of the Road festival will hold workshops. “The appeal is absolutely not about kitsch,” says Matthew Reynolds, owner of Duke of Uke, where he sells ukuleles costing between £15 and £1,000 and organises weekly workshops. “Sometimes you might play it tongue in cheek, but it’s a genuinely versatile instrument, with a sound of its own, that lends itself to all kinds of music.” The people I meet at his classes include scruffy twenty-something musicians who want to use the instrument in their music, a City boy who found one in his grandfather’s loft and accountants looking for a new hobby.

The ukulele is also gaining in popularity as a first instrument for children, with a growing number of primary schools offering it as an alternative to the recorder. Reynolds launched the Kitchen School of Music with his fiancée, Anne Larsen, to take the instrument into classrooms. “It appeals to children on so many levels,” he says. “It is playful and unintimidating, child-sized fingers fit round it, it’s as portable as the recorder and it can be played in class-sized groups. Kids have to practice a lot before they get a reliable sound from a guitar or many other instruments, but they can play along immediately on a ukulele by strumming one or two chords.”

A couple of lessons in, I’ve caught the bug. Not only was my uke cheap to buy and easy to start playing, its disarming silliness makes me feel less self-conscious about my lack of polish when knocking out scruffy cover versions of my favourite songs, helped by arrangements worked out by fellow enthusiasts and posted online.

An increasing number of bands and singer-songwriters are incorporating the ukulele into their music, giving amateurs like me more than jokey covers of pop songs to aspire to. The Anglo-French troubadour Jeremy Warmsley, Stephin Merritt, of the Magnetic Fields, Conor Oberst, of Bright Eyes and the eccentric London-based singer-songwriter Patrick Wolf are uke evangelists. Beirut, whose Balkan-via-Brooklyn folk was a Glastonbury highlight this summer, use the ukulele alongside squeezebox, mandolin and euphonium. Their front man and songwriter, Zach Condon, says: “I bought my first one because I thought it would look funny on stage, then discovered that it’s the most portable songwriting machine you can get. It took about a week for my fumbling fingers to get the hang of it, but after that I was recording with it straightaway. The timbre is really exciting. There’s something very human to the sound – true, sweet notes can ring out of it, but it’s rough around the edges. And the way it’s played has a hop-hop-hop that gets people excited. I take one with me everywhere now, and write almost all my songs on it. It definitely isn’t a novelty any more.”

Heading home from a workshop, I perch on a wall, pull out my uke and play quietly to pass the time. A couple of other people in the bus queue give me a smile, while a passing group of boys jeer. Then I hear a chink at my feet. A passer-by has taken me for a busker and thrown me 50p. I don’t think I’ll give up my day job just yet, but it’s encouragement, if encouragement were needed, to keep on strumming.

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