"The market is a community event - so why not have a community benefit?" said Mr Turnbull, whose company does the marketing and advertising for the event.
"We wanted to support a cause which covers the whole of the community, not just a particular group.
"And Wellington Free helps everyone from little babies through to your grandma."
In the past, the market's proceeds have gone towards the Martinborough Volunteer Fire Brigade - with $5000 raised last market season.
"Those guys give up their time, risk their lives every day and don't get paid - so the least we can do is help them out.
"Hopefully, this year, we can make even more money for the ambulance."
The market has been running since 2012 and attracts vendors selling a range of Wairarapa-made produce, such as gourmet meat, cheese, confectionery, whitebait, olive oil and craft beer.
Stall holders confirmed for this year include include Kingsmeade Cheese, Wee Red Barn, Peak Brewery, Juno Olives and Greytown Butchery.
Mr Turnbull said 24 stall holders have been confirmed, with more expressing an interest.
"I think stall holders are more inclined to come on board if it's for a community cause."
"Also, if they make a financial contribution, they're likely to put their best foot forward as a seller."
He said the market has been popular since its inception.
"Whenever I've been, there's been a good couple of thousand people wandering around. People enjoy listening to live music and sampling local produce in a lovely spot.
"It's good for Martinborough - people come over from Wellington and check out the other vineyards."
The first Te Kairanga Farmers' Market will be held on November 2 from 10am to 4pm, at Te Kairanga Wines, Martins Rd, Martinborough.
