Reports of grapes bursting with flavour and the potential for a once-in-a-century vintage have been coming from areas like Hawkes Bay and Marlborough.
New Zealand Winegrowers chairman and Bannockburn grape grower Steve Green said while Central Otago growers were ''pretty happy'' with their grapes, it was probably a bit too early to label it a brilliant season.
He said the season had started off cool but since January it had been dry and warm, concentrating the flavours in the grapes. Although he thought it would be a great vintage, there was still some time to go before they could declare so.
The harvest period is just cranking up in Central Otago and with about two weeks still to go until all the grapes were off the vines, growers would be keeping their fingers crossed for fine weather, he said.
Too much rain could lead to disease such as botrytis and frosts too cold would ruin grapes and could affect the vines for next year.
A light frost in the Alexandra basin this week saw growers dust off the helicopters and wind machines but, according to Drumsara vineyard owner John Matheson, growers were ''probably being a bit nervous''.
Central Otago Winegrowers Association president James Dicey, also a Bannockburn grape grower, said the season had been unusual. Some vineyards usually early to harvest were a bit later this year and vice versa.
Spring frosts last year had hit isolated pockets of grapes throughout Central Otago and therefore yield across the region would be down by 10% to 15%.
One of Mr Dicey's Pisa Moorings vineyard blocks had been severely affected by frost, had lost about 50% of fruit and was unlikely to cover costs, but an adjacent block was fine.
He also manages other vineyards in the region and said crop size was variable but overall, berries were all of good size.
Both Mr Dicey and Mr Green said the biggest issue facing the harvest was a major lack of seasonal workers.
''There's a major labour shortage in the region at the moment, a major backpacker shortage,'' Mr Dicey said.
He started harvest at his Pisa Moorings vineyard yesterday with a small team of Vanuatuan workers and was waiting for 50 more to arrive from Blenheim.
Mr Green said most wineries were looking for staff to help with the harvest.
While the main harvest is beginning, grapes for sparkling varieties had already been harvested.
Quartz Reef winemaker Rudi Bauer harvested grapes for his methode traditionnelle wines about three weeks ago and said he was very happy with the flavours.
He said while it would be some time before winemakers could see how 2013 wines would turn out, indications were that 2012 was a ''very strong year'' for both white and red varieties.
Staff at contract winemaking company VinPro were yesterday processing some of the first grapes to arrive at the factory. Assistant winemaker Dave Sutton said the coming three weeks would be the busiest for the them as they took delivery of grapes and began the winemaking process.
Central Otago has about 1600ha of vines, which average a yearly yield of 8000 tonnes, equating to about 5% of New Zealand's wine production.
