Noel Fielding and Julian Barratt crowned their decade-long journey from cult comedy oddballs to admired TV stars by audaciously headlining their own outdoor festival on Saturday. With room for 30,000 people, the country-park setting was pleasant, if inconvenient for public transport. Dozens of audience members came dressed as characters from the Boosh pantheon.

Oddly, considering this was essentially a comedy festival, the main stage was reserved for bands and DJs, while well-known stand-up comics were relegated to a smaller tent at the edge of the site. This meant minor rock acts including The Kills and Har Mar Superstar playing to thin crowds, while Andrew Lawrence and Frankie Boyle packed an overflowing comedy tent with their spectacularly tasteless routines about anal sex, paedophilia and Josef Fritzl.

Steeped in psychedelic whimsy and a very English surrealism, the Boosh belong to a much gentler tradition of homegrown comedy stretching back through Reeves and Mortimer to Monty Python and the Goons. They arrived for their main-stage headline show in grand style, dressed as space-age pirates for a glam-rock parody tune entitled Future Sailors.

Straddling a galleon in glittery silver jumpsuit, the ever-effusive Fielding assumed sex-symbol frontman duties from the off. The more lugubrious Barratt trailed behind in a blow-up dinghy. A deep-seated affection for pop music and its attendant youth tribes have always been woven into the Boosh's comedy. Their festival set allowed them to foreground this interest, especially Barratt's pretensions to being a sophisticated jazz aficionado.

Jazz was just one of the styles subjected to affectionate pastiche in a show that also embraced electro pop, punk rock, funk and heavy metal. Backed by a professional rhythm section, Barratt proved a very competent guitarist. Characters from the TV show including Naboo, Bollo and the seaweed-haired undersea hermaphrodite Old Greg all made appearances.

While the music was competent, the comedy was thinly spread. Aside from a few brief skits there was scant scripted dialogue or interplay between the characters. Instead, the Boosh preferred to indulge their pop-star fantasies to the hilt. During a cluster of indifferent funk-rock numbers a wearying sense of repetition set in.

They recovered in time for the inspired finale, which featured an army of punk pensioners and a Sweeney Todd-style number about eels. Fireworks, flamethrowers and confetti streamers cemented the sense of grand rock spectacle. There were flashes of genius in this event, but the experiment was only partially successful.

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