How many honours and prizes can you load on a 20-year-old pianist? For Benjamin Grosvenor, who last month carried off a Classical Brit and two Gramophone awards in the same week, the question is not academic. Ever since he won the piano section of the BBC Young Musician of the Year competition at the age of 12 he has been singled out for stardom, making his debut at the Royal Albert Hall and at New York's Carnegie Hall a year later. Last year, he became both the first British pianist in nearly six decades to be signed up by Decca, and also the youngest-ever soloist to appear on the opening night of the Proms.
But although he spent his teens giving concerts for local music societies in Essex and beyond, his parents and piano tutor Christopher Elton wisely kept him out of the limelight (pianist Freddy Kempf, another young BBC winner, was almost destroyed by such premature fame). After he was picked up at 13 by an agent who quickly lost interest, they moved him to another who understood the dangers of early overexposure. Meanwhile Grosvenor's piano-teacher mother also knew how to nurture his talent.
Elton, a Royal Academy professor, who has been his tutor for the past eight years, wryly recalls what had seemed an inauspicious start. He got an email out of the blue from Grosvenor's mother asking if he would listen to her nine-year-old son – "And I thought, oh my God, here we go again." The boy was almost wordlessly shy, says Elton. "In fact, it was several years before he and I had our first proper conversation – but from the first moment it was clear there was something extraordinary there. Not just an intense musicality, but real originality, a very unusual voice. In very difficult pieces he would get around the notes in a way that, though slightly clumsy, had enormous determination, and he played some exquisite Chopin." Ten years of practice, working eight hours a day – which, as Grosvenor points out, is routine for any day job – have led to the emergence of today's audience favourite, with his towering Saint-Saëns, bewitching Scarlatti, and dazzling jazz.
When I encounter him he's wordless again, but for good reason: he's watching a group of seven-year-old violinists go through their paces at a school in Lambeth, prior to showing what miracles can be wrought on the classroom honky-tonk. Grosvenor is here to give a workshop as part of the London Music Masters' Bridge Project, a scheme providing music tuition to underprivileged kids in inner-city boroughs. Is this, I ask, the prelude to a Lang Lang-style career as a pianistic Pied Piper? Grosvenor dismisses the idea with a diplomatic laugh, but says that if the project would like him to be one of their official ambassadors, he would be honoured. He has, indeed, since been asked, and accepted.
You soon realise not to expect soundbites from this young man. He thinks before speaking, and his replies have a simplicity which is of a piece with his life; it's rare for someone under such relentless pressure to remain so healthily grounded.
What did his mother give him? "Everything. My love of music came from her, and, crucially, she would practise with me. In the early days, we formed my interpretations of pieces together."
Is he glad that he had an ordinary state education – prior to being home-schooled from the age of 14 – rather than a specialist musical one? He replies that being a boarder at the Yehudi Menuhin School, which he looked at but decided against, would have disrupted his relationship with his elder brother Jonathan. Because Jonathan has Down's Syndrome and is partially sighted, Benjamin has always acted as his protector. "We're a very close-knit family," observes this youngest of five brothers; until a year ago, he shared a bedroom with Jonathan, who often comes on tour with him, the pair always being chauffeured by their mother. It's an honourable tradition that classical soloists should travel with a family entourage –Maxim Vengerov and Evgeny Kissin did so until well into their thirties – but, as Grosvenor points out, when you're giving 15 recitals in 17 days, as he recently did in Germany, such assistance is vital. He loves tours, where one of the very few drawbacks can be his requirement for a vegetarian menu. Is that a stand on principle? "Yes, but also by inclination. When I was 14 I found myself thinking that, in an affluent society, there was no real reason to eat meat – the idea that something died and I was eating it just for pleasure ...."
Does he enjoy his fame? A pause, a laugh: "Well, I prefer playing the piano. It's great to have your work recognised, but it doesn't affect the way I think about myself. I'm just constantly trying to improve." Known for dressing more casually than the average concert pianist, he represents the young, popular face of classical music: does he feel he's being marketed as a commodity? "In a way, I suppose. But my mother chose the red shirt I wore for this year's Prom – I'm not big on clothes, so it's good to have a feminine input, and you don't want to seem old-fashioned. It's important for audiences to feel close to performers."
He tries not to read the articles now proliferating about him, and he's not a great reader of his reviews, but that's partly because he records his own performances and listens back with a hyper-critical ear. He also listens fanatically to recordings laid down by the great pianists of the past, most notably by that German Beethovenian Wilhelm Kempff, whose amalgam of classical restraint and emotional intensity represents the ideal Grosvenor is striving for. In contrast to the young Korean whirlwind H J Lim – who recently recorded all Beethoven's 32 sonatas in a year – Grosvenor makes it a year's project to master just one, but there's no comparison between the results. Something else Grosvenor shares with past masters such as Alfred Cortot and Artur Schnabel is what he calls his "asynchronicity of the hands", whereby the left will come down on the keys a microsecond before the right.
"When I was 12 I did it naturally, but now it's a conscious device that can add intensity to a phrase." In his Chopin, it creates ravishing effects.
That is one of the pleasures in store for those who will be at the Queen Elizabeth Hall on Wednesday, when Grosvenor makes his eagerly awaited South Bank debut. He will begin with a Bach partita, and then progress via Chopin, Scriabin, and Granados to a Blue Danube extravaganza which will give his showmanship free rein. Will he suffer from nerves?
"When you are playing a recital programme for the first time, it can be scary. But when I walk to the piano my nerves usually dissipate, and by the time I'm at the keyboard I feel quite calm."
Benjamin Grosvenor plays at the Queen Elizabeth Hall, London, on Wednesday (southbankcentre.co.uk)