Stephen Hill, 64, has spent weeks watering the monster plant in the front garden of his home in Bradwell on Sea.
Now he reckons it has broken the UK record after smashing the 15ft barrier.
“If you look it up, the UK record for the highest hollyhock is 15ft and this is 15ft 4in,” said the retired Ford production worker.
“I’ve been growing them for about eight years.
“They all did well this year, but this one has done particularly well.
“It just went mad – I couldn’t believe it.
“I kept measuring it every week.
“I’ve been putting gallons of water on it every time the top started to droop a little bit in the warm weather.
“And I’ve got guy ropes holding it, so it wouldn’t blow over if the winds came.”
Stephen, of Bate-Dudley Drive, says passers-by have been stopping to admire the giant plant, which has pink flowers.
“We’ve had a few people look at it in amazement, but hollyhocks do look slightly eccentric,” he said.
“I think the Guinness Book of Records are only interested in world records so I’m not sure how we would register this one.
“I was thinking maybe I’ll get on to the Royal Horticultural Society – they might be able to point me in the right direction, or might be interested themselves.”
He continued: “I like gardening – both my wife Jayne and I enjoy it.
“This isn’t the most interesting plant, it’s just the height.
“It’s only got two flowers on top. There were a lot more, but my grandchildren come and visit every Thursday and they have been picking a few of them, so it’s a bit stripped.”
The world’s tallest hollyhock was 7.4m – 24 ft 2in – and was recorded in Israel in 2021. The previous record had remained unbroken since 1978.
Asked if he had any tips for growing goliath hollyhocks, Stephen said: “Lots of horse manure – that’s the secret!”