Reading Festival, Richfield Avenue, Reading

How do you wow a festival crowd? Robert Smith does it with hit after hit, while Florence just gets stuck in

Fifty-three years old, face the size of the moon, and the coolest man in all of Berkshire, Robert Smith sips a glass of white wine and shuffles back to the microphone stand. He's not in any kind of hurry. When you've seen The Cure, you've really seen The Cure. Last summer's three-hour Bestival show has already passed into legend, and their headlining set at Reading 2012, encompassing 32 songs, is almost as epic.

During my youth as an Eighties goth, there were countless reasons to be sniffy about The Cure. They felt like the Softy Walter option: too cuddly, too winsomely appealing to girls who wanted to take Smith home and mother him. But these objections fade with time, and you're left with a mainly magnificent body of work, performed by a band in the mood to give the public what it wants, whether that be the immaculately romantic swoon of "Just Like Heaven" or the juddering gloom-rock of "One Hundred Years".

Yes, there are long, faith-testing stretches of up to five non-famous songs, during which faint-hearted dilettantes drift away, but patience pays off when the band – the handsomeness of disgustingly well-preserved bassist Simon Gallup balanced by former Bowie guitarist Reeves Gabrels – eventually strike up "A Forest", and seasoned Cure-watchers reach for their stopwatches. It lasts a modest six minutes; I've seen it go on for 11.

"Now, some encore songs," Smith says to almost tangible relief, and they rattle through the big hits: "The Lovecats", "Let's Go to Bed", "Close to Me", "Why Can't I Be You" and "Boys Don't Cry". Near the end, the statement-shy singer apologises for his diffidence. "It's weird, 'cos even explaining why I don't talk, I find impossible to say. But it's all in here." He taps his head. "I'm thinking it, trust me."

His strongest statement, however, is visible every time he appears on the big screen. The Cure may not be a band given to political slogans, but Smith has something powerful painted on his guitar in this summer of jingoism and jubilees. "2012: Citizens, Not Subjects."

At 11am on Saturday, the main field is eerily empty. In the far corner, however, there's pandemonium. "This has got to be the best worst-kept secret in all the UK," says Billie Joe Armstrong of Green Day, playing an unscheduled, but widely announced, show in the Radio 1 tent. If anyone hadn't read about this late addition online, word-of-mouth does its work the old-fashioned way, and a human stampede heads towards the marquee, ushered along by extra stewards with bullhorns and specially erected fencing towards what amounts to an authorised flashmob (if that isn't an oxymoron).

I remember interviewing Green Day around the time of their game-changing, genre-defining pop-punk album Dookie, and praising them on what I took to be a sly satire of feckless youths who just want to sit around, drink beer and masturbate. "Satire?" they said, confused. From that moment on, we were never going to see eye to eye, but it's been hard not to admire the way in which they've become steadily more politicised and Clash-like while their hydra-headed spawn have become more banal and Busted-like.

It's also impossible to watch them without conceding that that is how you put on a rock show. During a set dominated by the hits ("American Idiot", "Basket Case", "Longview"), Armstrong and co shamelessly exploit every crowd-pleasing trick in the book. The improbably baby-faced frontman catches a fan-thrown skipper hat and does an exceedingly camp dance with it on, indulges in a bit of pantomime when a bouncer has to drag him offstage to make way for the next band, and operates the best gimmick of the entire festival: a mechanised toilet roll thrower.

Another band I'd never listen to for pleasure, but whose Reading set I have to applaud, are Florence and the Machine. Spirits are beginning to sink into the mud as the rain falls, but Florence Welch delivers a mistressclass in how to turn an unpromising situation around. Posh she may be, but she's no princess. Puddles are forming around her Art Deco mic stand; her floor-length mesh dress is dripping wet, but the foghorn-voiced Elizabeth Siddal lookalike doesn't hide. Declaring that "these ballet pumps aren't doing me any favours", she takes her shoes off and, like her inspiration Kate Bush, throws them in the lake. Almost literally. Welch's willingness to get right stuck in is reciprocated by a crowd that builds human pyramids four people high. And I can now add "ballet dancing in the mosh circle" to the list of things I've never seen before.

The undisputed Song of the Festival is "212" by Azealia Banks. The Harlem 21-year-old's potty-mouthed hip-hop hymn to cunnilingus (and more) is everywhere this year. If it's playing in a clothes stall, it turns into an impromptu party. If it's playing backstage, VIPs actually stop schmoozing and dance. If it plays over the main stage PA between bands, the entire field starts booty-shaking. And when she plays it herself on Saturday evening, the Dance Tent goes ballistic. Hey-oh, hey-oh …

In their top hats and tails, a magnificent new album up their sleeves, The Hives are the surprise hit of the weekend, their garage-rock cabaret packing even more punters into the tent than Green Day. The same can't be said for big-haired post-hardcore berserkers At the Drive-In, who mark their return after a decade's hiatus by wheeling a tea urn to Ride of the Valkyries then, like cleaning ladies, wielding brooms on the stage: literally sweeping the boards clean and starting again. A neat symbolic stunt. Shame hardly anyone sees it.

The most rock'n'roll performance comes from a band who aren't rock'*'roll in the literal sense. Canadian post-electroclashers Crystal Castles are so goth their balloons are black, but there's nothing reserved about purple-haired singer Alice Glass, crowdsurfing or diving to her knees in the photo pit and grabbing handfuls of woodchip. She's half Powerpuff Girl, half Iggy Pop.

The pick of the smaller stages are Turbonegro, a veteran band of Scandinavian bears (in the gay slang sense) wearing sailor caps, bowler hats and pith helmets, playing hard rock songs with titles like "I Got Erection". They're gloriously out of place. As opposed to simply not knowing where you are. Like Santigold, who undoes a fine set of skank-funk with three little words. "Thank you, Leeds!"