It’s three hours before showtime and members of an orchestra are seated onstage in the garden of a 1,000-year-old Benedictine monastery outside Cologne, Germany. On cue, the neatly coiffed, black-clad musicians slowly raise their instruments, purse their lips and begin playing the opening passage of Igor Stravinsky’s The Rite of Spring. Just then, a sound technician abruptly cuts them off. The carrot flutes were too strong and he couldn’t hear the leek violin. “One more time,” he says. “Starting with the cucumber.” You may also be interested in: • Did Syria create the world’s first song? • The cheeky gnomes taking over a city • Japan’s art of naked friendship This is Vienna’s Vegetable Orchestra: a 10-piece ensemble from the city of Beethoven, Brahms and Mozart that plays music with instruments made entirely from fresh produce. Over the past 21 years, the group has played nearly 300 shows at packed venues around the globe and performed everything from classical with cabbage to techno with turnips in a rich, rhythmic ratatouille. The orchestra recently released its fourth album after a successful ‘Krautfunding’ (‘herb-funding’) campaign and is showing the world that, actually, you can play with your food. “Vegetables are unpredictable,” said Susanna Gartmayer, who plays the carrot marimba, radish bass flute and a dozen other edible instruments in the group. “No two pieces of produce are the same. It’s a challenge.” Unlike traditional instruments, which can last for hundreds of years, vegetable instruments quickly go bad, so the orchestra has to create new ones each time it plays. The morning of every show, this group of artists, novelists, architects and designers goes to local markets with a detailed shopping list and carefully combs through the crates. After pounding on the pumpkins, pawing through the parsley and peeling back the onion skins to select just the right produce, the musicians carve, slice and drill their fresh finds into performance-ready instruments. Once the veggies are peeled and cut they may only last about six hours, and whatever the musicians don’t use gets boiled down into a soup that’s served to the audience after the show. This media cannot be played on your device. But as the group arrived back at the Brauweiler Abbey that morning and unloaded their haul for the evening show, they noticed a big problem: someone forgot the aubergines, and there weren’t enough courgettes. While a runner hurried back to the market, the remaining musicians grabbed their knives and power drills, transforming the dressing room of this Zen-like monastery into a construction site. During the next two hours, hollowed-out carrots, cucumbers and calabashes slowly became horns and flutes; severed peppers morphed into trombones; and sliced celeriac and pumpkins turned into bongos and drums. Each musician makes between eight and 25 instruments per show, and as the performers gradually tested and twisted their produce into tune, a cacophony of trilled scales, percussive thuds and surprisingly resonant notes sang through the sanctuary. “It all started as a joke,” said founding member Matthias Meinharter, scanning a room full of veggie guts and breathing in what smelled like a compost bin. As he remembers it, he and three of the orchestra’s other members had signed up for a performance-art festival at their university in Vienna. “We were brainstorming what we could do, and we thought: ‘What is the most difficult thing to play music on?’,” he said. “We were making soup together at the time, and one idea led to another.” Twenty-one years later, the orchestra has played at London’s Royal Albert Hall, the Shanghai Arts Centre and was invited to a Ukrainian oligarch’s mansion to perform at Paul McCartney’s 60th birthday. “I think he liked it,” Meinharter said. “He’s a vegetarian.” The group has also been listed in the Guinness World Records for ‘Most concerts by a vegetable orchestra’ and has inspired a few other biodegradable ensembles to sprout up around the world, including the London Vegetable Orchestra and Long Island Vegetable Orchestra. While the project may have started as a gag, these days its members take their craft very seriously. “Many people think we’re kind of cabaret or just a funny performance,” Gartmayer said, drilling holes to make a carrot xylophone. “But they’re surprised to understand that there’s actually a lot of sonic potential in vegetables, and that we want to make really interesting music.” There’s actually a lot of sonic potential in vegetables The orchestra has invented more than 150 instruments over the years – and for many members, that’s half the fun. Some are ready-made items from the market: crunching dried onion skin in your fist sounds like a rainstorm, thumping a pumpkin with your palm resembles a bass drum and rubbing two leeks together as a bow and body creates a squeaky string section. Others are cut-and-carved creations resembling traditional instruments: parsnips, courgettes and peppers make good wind and brass instruments, while hollowed-out gourds are percussive. The most complex are transformer-like hybrids that combine two or more vegetables. Want to imitate a saxophone? Attach a severed bell pepper to the end of drilled cucumber, add a carrot mouthpiece and you’ve got the ‘cucumberphone’. Need a slightly deeper pitch? Swap the cucumber for a courgette and you’ll have a ‘courgette clarinet’. “One of the most fascinating things about touring is learning how food differs around the world and coming up with completely new instruments,” said calabashist and pumpkinist Jürgen Berlakovich. In South-East Asia, the group discovered an elastic garlic grass that made a great bass string. In the US, they found markets that sell giant agave leaves, which can be used to shake kidney beans like a maraca. In China, the water radishes are bigger. In Italy, the cucumbers are smaller. In Siberia, the vegetables are expensive. And in England? “Turnips,” Meinharter said. “Lots of turnips.” Despite covering a few Kraftwerk and classical pieces, the Vegetable Orchestra mainly composes original material, which can range from dark and hypnotic electronic sounds to beat-oriented house tracks. To do this, they attach tiny condenser microphones and little pickups to the veggies to amplify their natural tone and, as Berlakovich said, “to make them come alive”. But when they first set out, learning how to play the parsnip wasn’t the only challenge: there was no way to write music for food. Because veggies are shaped differently from crate to crate and country to country, they can sound different, too. So instead of notes, the group developed a sort of timeline showing when the instruments come in and a graph of high and low pitches. “No-one else could read it,” Berlakovich said. “It’s like a secret code.” At the end of their sound check, the orchestra descended from the abbey’s outdoor garden stage and quickly re-wrapped their instruments in moist towels. The show was set to start in 90 minutes, and the veggies were in trouble. “It’s unusually hot today, which makes the vegetables brittle and break,” said founding member Barbara Kaiser, holding up the severed head of a cabbage. “But they like to die dramatically on stage.” When the sun descended under the abbey’s spires, a team of tuxedo-clad ushers lit fire torches around the complex’s manicured courtyard and opened the doors. Soon, hundreds of well-heeled Germans were strutting through the vaulted walkway, many asking one another if they had ever heard of this Gemüsegruppe (‘vegetable group’) on the way to the Champagne bar and their seats. As the all-black-clad troupe took the stage and steadied their water radishes, a few nervous giggles echoed through the garden. Berlakovich soon kicked into the warbling root prelude with a thumping bass pumpkin beat, two members tapped wooden spoons on dried squash, and the carrot section looped in a fluted melody, sliding the song into a trance-like tribal rhythm. By the third song, the audience was tuned in to the texture of the ambient compositions: the crackling of celery stalks, the rumbling urgency of onion skin, the groovy claps of aubergines and the wind-like effect of rubbing two parsley bouquets together like pompoms. By song four, nearly everyone at the 500-person show was bobbing their heads along – except for one serious, older-looking woman wearing a black dress in the front row. Towards the end of the set, bits of dried veg-struments were flying off the stage with each tap, clap and pluck. The group shook the abbey’s foundations with a take on German Krautrock, hooking distortion pedals and microphones into heads of cabbage and strumming their waxy leaves like guitars as shredded greens littered the stage. By the time the orchestra culminated their final song by rolling a legion of legumes and potatoes down a ramp, the once-clean stage looked like an exploded farmers’ market. The orchestra then bowed to a standing ovation and began mopping it all up. “For me, this is still multi-sensory performance art,” Meinharter said. “The audience can hear the music, smell the music, see the music and then taste the music.” After the show a swarm of people surrounded the musicians, eager to buy CDs, snap pictures with the group and taste what they’d just heard. In keeping with a 21-year tradition, the performers offered their instruments to anyone who might want to go home and practice jamming on the produce themselves. Gartmayer asked if anyone was interested in her pepper trumpet, and the older woman in the black dress reached out her hand, stuffed it in her purse and walked briskly towards the exit. When she thought she was out of sight of everyone, she pulled the pepper from her purse, put it to her mouth and gave it a good, long hoot. Custom Made is a BBC Travel series that introduces you to custodians of cultural traditions all around the world. Join more than three million BBC Travel fans by liking us on Facebook, or follow us on Twitter and Instagram. If you liked this story, sign up for the weekly bbc.com features newsletter called “If You Only Read 6 Things This Week”. A handpicked selection of stories from BBC Future, Culture, Capital and Travel, delivered to your inbox every Friday.