By Ed Davey
BBC News, London
Litter pickers in Hyde Park have had their work cut out
Not everyone celebrates when the sun comes out - park workers in London say there is a tenfold increase in litter left behind by sun-worshippers.
As the dust settled following the three day sunny spell, London's park cleaners faced a mammoth clean-up task.
They warn that when the sun comes out an unwanted mess of bottles, wrappers and plastic bags is left in its wake.
In recent days London councils have had to put on extra services and take cleaners off other duties to cope.
David Tibbatts is general manager of Greenspace, a charity that looks after many London parks.
He said: "You are looking at a tenfold rise in the amount of litter left in parks.
"When the sun comes out a lot more people are using parks - and with that comes far more litter.
"It is not just the high numbers of people causing the problem, it is the way parks are used with more picnics and barbeques."
Highbury Fields in Highbury, north London, was one of the affected parks.
By 2100 BST on Tuesday a swathe of litter covered the park from top to bottom.
Highbury resident Tom Stirzaker, 25, who works for a pharmaceuticals website, said: "By the end of the day it was an absolute disgrace - it was like a war zone.
"There were bottles and litter strewn across the whole park - it's a real shame."
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He added: "People come to enjoy the park but they are not responsible enough to leave it in the state they found it."
Highbury resident Katie Dawson, a Green Party councillor, is used to seeing her local park trashed.
She said: "When there is a heat-wave, pretty much every park in London gets wrecked.
"Waste collection services need to have more of an in-built flexibility - the same as other services do when it snows.
"In the summer they should bring along more disposable bins for people to recycle their rubbish."
Mr Tibbatts warned the experience in Highbury was indicative of how London's open spaces were treated during sunny weather.
He continued: "It just stuns me that having enjoyed a park a group of six people will leave all their empty bottles and rubbish behind.
"Most parks teams have to ramp up their staff during the summer - or other maintenance does not get done because their resources are diverted."
A spokesman for London Councils, which represents the city's local authorities, said council workmen have had to spend the majority of their shifts cleaning up parks after the recent weather.
He said: "The advice to Londoners is simple - put your rubbish in the bins provided by your local authority.
"If you can't find one or bins are full, take your rubbish home with you.
"Public spaces belong to us all - and each of us has a responsibility to keep it tidy."