Cool weather delays region's vine growth

Cool spring weather has put vineyards about a week behind their usual development, grape growers say.

Spy Valley general manager Blair Gibbs said the vines were looking good but were behind normal growth because of the cooler ground temperatures and less sunshine in October.

This week's rain was not helpful, especially for earlier flowering varieties such as chardonnay, but the impact depended on the vineyard location, he said.

The winery needed to get through flowering before it could make accurate yield predictions, Mr Gibbs said.

Plant & Food Research senior scientist Dr Mike Trought said the wine industry was aware it needed to manage yields to ensure there was not an overproduction of grapes.

Lower winter and spring temperatures had delayed growth by about a week, he said.

"There is the potential, and I stress potential, for the yields to be slightly up on average, so we don't want a particularly warm flowering as that could push the yields up."

The cooler weather and rain could also push yields downs, Dr Trought said.

Flowering was under way, but how quickly it progressed was weather dependent.

At this stage, most vineyards were busy with wirelifting and spraying, he said.

Fairhall Downs co-owner Stuart Smith said both his chardonnay and pinot noir vines had started to flower.

However, he said he was still waiting on the sauvignon blanc.

The sauvignon blanc crops were looking slightly above average, while the pinot noir and chardonnay were looking average, he said.

However, an accurate yield prediction could not be made until after flowering, he said.

The New Zealand Winegrowers chairman said, in general, it would have to be a very cool flowering to have a significant impact on yields.

The wet weather had not caused problems for the vines, though it had made it hard to keep up with mowing, he said.

Bladen Wines co-owner Dave Macdonald said the vines were about a week behind their normal development.

He gathered it was going to be a hot dry summer, which would be great for his vines.

However, he always took weather reports with a "grain of salt".