Grant Taylor, of Gibbston's Valli Vineyards, said his winery was not affected by labour issues because it was relatively small, but a post-harvest debrief by wineries last year found the labour shortage to be the single biggest factor affecting quality.
"People just couldn't get in and do the work they needed to do to make the fruit that much better."
Competition from cherry growers and immigration changes by the new Government exacerbated the issue.
Despite the challenges, 2018 has been a fruitful year for Central Otago wine, with the 11,358-tonne harvest up 36% on 2017.
Mr Dicey, who is past-president of the Central Otago Winegrowers Association, said it was the warmest, driest growing season for a "very long time".
By comparison, the 2017 vintage was a cool one, producing much lower yields but "very intensely flavoured" grapes.
Looking ahead to next year's vintage, vines were hit by a major frost on October 13 and snow on November 19, but appeared to have "dodged a bullet".
"The vines have recovered significantly, and so long as the weather over the next month or so is good, I don't believe we're going to see any negative impact on yield."
Mr Taylor said last summer was 25% warmer that the long-term average, which was a "pretty incredible figure".
As a result he made almost twice as much wine as last year.
"These are the sort of years that make the bank managers happy, as well as the winemakers."
As for the 2019 vintage, it was "so far, so good".
Ample spring rain meant vines were going into summer with plenty of moisture in the ground.Because of Gibbston's higher, cooler climate and slower bud development, it escaped damage from October's frost, he said.
Central Otago has just over 1900 hectares planted in vines, of which 76% are pinot noir, the highest concentration of the variety in any of the world's wine regions.
