Duke of Uke: Why is one of London's quaintest ukulele shops facing closure?

I'm not sure if Richard Curtis himself could improve upon the styling of Duke of Uke, the little ukulele shop in Spitalfields. A quaint London street, an old-fashioned store front, a shop piled up with instruments, music stands and a large black and white photograph of George Formby over the counter.

The casting is perfect, too: Matthew Reynolds, owner of the shop, is dressed as if he has just wandered off the set of Women in Love; while I'm there, a musician wearing an implausible hat and a tweed suit drops by to tune up; a Japanese girl arrives on a bicycle and sits at the piano, picks up a uke randomly, and starts playing. Two pretty young girls holding hands come in to look around. On second thoughts, perhaps it's all a bit over the top for even our schmaltziest film director.

Ukuleles are officially at the height of their popularity, 40 years after Tiny Tim first invited us to "Tiptoe Through the Tulips". Last month's Rolling Stone magazine reported that uke sales are up 300 per cent in America, after artists such as Taylor Swift and Pearl Jam's Eddie

Vedder have made a big thing of them. Dhani Harrison, son of the great enthusiast George, says you can't help but love them: "They're endearing". If you have an idle moment, have a look on YouTube at Jake Shimabukuro performing "While My Guitar Gently Weeps" in Central Park. "A god," someone commented eight and a half million hits ago.

My first introduction to the ukulele was not so cool, I'm afraid. I'd discovered that Warren Buffett plays one. It's his little party piece, something he performs annually at the Berkshire Hathaway shareholders' meetings. After delivering his address on the state of the financial nation, Buffett plucks and strums away. It shows he's human. No other instrument could possibly convey this egalitarian message as succinctly as a uke. So humble – only four strings – and yet so charming.

It was this charm that first seduced Matthew Reynolds. A fine art graduate, he had always played the guitar and drums for fun until someone gave him a ukulele 10 years ago. "I wasn't really interested in it at first," he says, "until I realised that all the music I liked from the Twenties and Thirties had sheet music written for it. There was a whole history to it that I wanted to find out about."

The ukulele was invented in Madeira in the 18th century and taken by Portuguese immigrants to Hawaii in the 1870s. There it was taken up the Royal family who became besotted with it and in 1915 it was launched at the Panama Pacific Exposition in San Francisco, promoted by the Hawaiian tourist board complete with hula dancers. "The thing about it is that it is one instrument with all these different tonalities," explains Reynolds. "You don't get that with anything else. Guitars all sound the same."

I decided to learn the uke for several reasons. One was that I wanted to do anything that Warren Buffett did (except follow the advice about not borrowing money) and another was that I play the piano and think that reading music must be very stimulating for the remaining grey cells. But my biggest reason was my husband. He loves music but has never learnt to play an instrument. I wanted him to experience the pleasure that comes from playing music. He's a very sociable fellow and the ukulele is a sociable instrument. It sounds best in a group and the beautiful part is that the sound the group makes is determined by the best people in the room, not the worst.

Back in January of last year, we began to take ukulele lessons with a group that met in the evenings at Reynolds's shop. To begin with, we felt like idiots. Our fingers seemed massive and clumsy. How could you hold down two strings at once with these great big sausages? How was strumming achieved? You can't play without rhythm, but what if you've got none? And the big question, of course, was why did everyone else in the group seem to get it and not us?

About half-way through the course of 10 lessons that run four nights a week at the Duke of Uke, something clicked. It was like learning shorthand; one day, with practice, you suddenly just get it.

I'll never be good at it – I don't have the time – but when the mood takes us, my husband and I will bang through "Will You Still Love Me Tomorrow?" and it's fun. Some of the other students were precociously talented, one of them a young American man who said he was studying in London for his PhD and so he had loads of free time on his hands. The rest of the group covered most London types, with no age or gender emphasis and, thankfully, we were not the oldest people there.

The alarming news now is that the Duke of Uke is closing. Their landlord has declined to renew their lease, so they need to find an alternative shop locally that has a basement they can convert into a recording studio, and a space big enough to do all their classes. In a way, they are the victim of their own success because the presence of the shop must have helped to make the street trendy – and more expensive. Reynolds runs the shop in a rather laid-back way (they open at midday, for example, and don't make anything as tawdry as a profit) which convinces me that they will somehow survive.

The publisher John Brown had similar thoughts when he temporarily managed the Ukulele Orchestra of Great Britain. "I did it because I'm a massive fan. I knew they had a lot of potential but sometimes I would suggest a more logical way of doing something and it wouldn't work." He continues, instead, in his role as their Roving Ambassador. The Orchestra's biggest night was their Proms debut in 2009 which was a sell-out. Six thousand people came, more than a thousand of them carrying a ukulele. It looked like the St Valentine's Day Massacre, walking the streets around the Albert Hall.

I hope the Duke of Uke survives. It's a gentle thing in a rough world. Reynolds is busy looking for a new shop and, next week, is holding benefit concerts in the crypt of nearby Christ Church, Spitalfields (see dukeofuke.co.uk for details).

Taylor Swift, incidentally, first learnt to play a 20-string guitar. Makes you think, doesn't it?

The Duke of Uke, 22 Hanbury St, London E1