He's been chairman for 16 of its 39 years, has presided over the raising of £50,000 for charity and on one day of the year he becomes Mr Pumpkin.
It is a fitting role for the chairman of Soham Pumpkin Fair.
On Saturday, through the green and orange costume, Mark Williams was beaming as he looked on while a warm early autumn day brought in record crowds.
'There are not many dates in late September when you can stroll around in shirt sleeves, stop off for a barbecue and enjoy a real family day out,' he said.
'Mr Pumpkin came out about 14 years ago and it has rather become a tradition. It doesn't seem to scare many any more – children I used to frighten now come up and yell 'hey Mr Pumpkin'.'
He has considered hanging up the costume 'but my youngster daughter keeps telling me to carry on, so I do'.
The serious side of business, though, is the amount it raises for charity, up to £3,000 now each year.
It wasn't all pumpkins as The Ely Youth Choir, primary schools, majorettes and a Beatles tribute combined to entertain the crowds.
Aside from competitions for pumpkins that included the heaviest, the competition to find the biggest sunflower head and the tallest sunflower drew considerable support.
There was a special welcome too for Beth Green who opened the fair.
The pumpkin committee honoured her after the mum-of-four had previously been voted 'person of the year' for her voluntary work that included raising thousands for Meningitis UK.
On Saturday, through the green and yellow costume, Mark Williams was beaming as he looked on as a warm early autumn day brought in record crowds.
'There are not many dates in late September when you can stroll around in shirt sleeves, stop off for a barbecue and enjoy a real family day out,' he said.
Mr Williams describes himself as 'a non-Soham, Soham person' meaning he's lived in the Fens town for as long as he can recall but was born outside of it.
'Mr Pumpkin came out about 14 years ago and its rather become a tradition,' he said. 'It doesn't seem to scare many any more – kids I used to frighten now come up and yell hey Mr Pumpkin.'
He has considered hanging up the costumer 'but my youngster daughter keeps telling me to carry on. So I do.'
The serious side of business, though, is the amount it raises for charity, up to £3,000 now each year.
'This year is definitely looking to be a record,' as he scurried off to start the first of three ferret races.
Caron Martin of Long Stratton presided over 30 minutes of ferret mayhem, encouraging modest bets on which of four ferrets would win a return race through specially constructed tubular tunnels.
Ivan Paul, 59, of Whittlesey was on hand to show a steady stream of visitors what keeping ferrets is all about- he's been a ferreter for 50 years.
He's one of the leading members of the Cambridgeshire Ferret Welfare and Rescue Society whose numbers come from most of East Anglia with one notable member joining them regularly from Cumbria.
Mr Paul was formerly a pest controller but ferrets have and remain his speciality and he's worried by those who buy them as pets without appreciating their needs.
'In reality they are low maintenance, and cost less than 50p a keep,' he said.
'However people don't look after them properly and we end up with them.'
Working ferrets still get requested, he says, once people realise they are an effective way of removing rabbits from their gardens or allotments.
Ferreters - or warreners as they are often called - like to race their pets for fun and to raise money for charity.
He's delighted many young people are joining the society and even the wives, he says, like to play an active role.
'People often grow up with ferrets in the family and so take them on themselves,' he says.
But it wasn't all pumpkins and ferrets as The Ely Youth Choir, primary schools, local majorettes and a Beatles tribute combined to entertain the crowds.
And aside from competitions for pumpkins that included the heaviest, the competition to find the biggest sunflower head and the tallest sunflower drew considerable support.
There was a special welcome too for Beth Green who opened the fair. The pumpkin committee honoured her after the mum-of-four had previously been voted 'person of the year' for her voluntary work that included raising thousands for Meningitis UK.
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