The biggest month-on-month sales increase over the past year was in March where Trade Me saw 62 per cent growth on the previous March.
The category is up 24 per cent in sales for the year ended June 2014, compared to the previous year.
Other categories averaged between 2 and 5 per cent growth a year.
"Ride-on mower sales have been growing quicker than a lawn on half a tonne of cow poo," Mr Hunkin said.
He put the impressive growth for both new and second-hand ride-ons down to an increasing number of people owning lifestyle blocks with lawns large enough to warrant one.
"Given ride-on mowers cost a fair whack, trustworthiness and assurance of a good price are pretty important factors," Mr Hunkin said.
Expert Mowers director Robert Cameron said the popularity in the mowers was the result of the large range available and a lowering in price which meant you could buy a new ride-on from $3500. Prices can go up to $30,000.
"They were a bit of a novelty in the early days," he said. "Now there's such a variety and choice around and price-wise they've actually come down in price and gone up in specifications and performance level."
Some of the newer mowers were also smaller and more nimble which meant that people were buying ride-ons from his West Auckland store for sections just over 1000sq m.
Mr Cameron said they were proving popular with the older generation who wanted a mower they didn't walk behind for health reasons.
And they were just as popular with men and women.
"It's become a more user-friendly type of operation with the ride-on mower, and the latest machines are much easier to drive than the earlier ones were."
There was a big push by the big brands such as Husqvarna and John Deere to sell ride-ons at Fieldays and this resulted in a huge influx of second-hand machines listed for sale a few months later.
Other sales categories growing significantly each year included building and renovation, industrial supplies such as welders, trade tools, building materials, electric appliances and the like, farming supplies, home DIY and homewares.
New mower makes light work of huge lawns
Debbie Kelly no longer dreads mowing the lawns thanks to her four-wheel toy.
The mother-of-two bought a Husqvana 4WD ride-on mower in April after spending hours behind an old motor-mower around her lifestyle block. It cut the time it took to trim the grass by a third.
"It's a joy to go out and do it. It's not a bore and a chore any more. You think, 'I could just pop on and do a five- to 10-minute job around here and it's all nice and tidy'."
Mrs Kelly, her mother and sister live in separate houses spread over more than 13ha in West Auckland. Using a standard push lawnmower it had taken three hours to mow the lawns of two of the three properties, not including the paddocks.
"And none of them were flat so it was always a really big effort and you had to do it over more than one day because you ran out of puff and inclination."
She now did the lawns of all three properties in less than an hour in one session and it also used it to trim the grass in the paddocks when needed.
"It encourages you to do it more often by having a ride-on, and it's quite economical as far as the petrol is concerned."
It was also quite relaxing.
Before purchasing her new toy, she had been given a second-hand ride-on to use in the paddocks but described it as a dinosaur that was unreliable and scary to drive.
So she could not believe the vast improvement when she test drove the new ride-on which had a steering wheel and 4WD and which she chose because it was easy to drive and felt safe.
The little bit of luxury had set her back about $12,000, but she said it was worth it for the extra time and fun it had given her.
