Marlborough wine companies bring in grapes ahead of 'D-Day' rain event threatening crop losses
Marlborough winemakers are racing against the clock to bring in the crop ahead of the remnants of Cyclone Debbie hitting the region full force on Wednesday.
Reports of wine companies turning away disease-riddled fruit are already swirling, and the heavy rain forecast for Wednesday is only going to increase the disease pressure.
Trucks and harvesters have been going full bore the last few days as companies bring in grapes, some not quite ripe, instead of leaving them on the vines to the mercy of the weather.
Viticultural consultant Murray Paterson said rain in the vicinity of 100 millimetres would set "the cat among the pigeons", however he and industry leaders were confident they could deal with less.
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Paterson said the rain could be a problem for grapes reaching ripeness, but a shortage of sunshine in March meant many blocks in the region were still short on sugar and not ready to pick.
Grapes that had a sugar content of less than 18 brix had thicker skins, making them less likely to split in the rain. This reduced the risk of the fungal rot botrytis getting inside, Paterson said.
He said there was a lot of botrytis around, so the streets of Blenheim would be devoid of backpackers and other harvest workers who were out in the vineyards cutting out rotten bunches.
The Viticulture Practice owner Lex Thomson said between 7 and 8 per cent of the fruit on one block he monitored was affected by botrytis. Wine companies usually had a threshold of 5 per cent.
"The thing about botrytis is if it gets good conditions, warm and wet, it can reproduce quite rapidly. So tomorrow will be crucial," he said.
"You don't get good years every year - we're at the mercy of the weather."
Wine Marlborough chairman Rhyan Wardman said botrytis would not have an impact on the overall crop size. It was not the healthy harvest of last year, but he said that was an outlier.
"It's the reality of cool climate viticulture, nobody is panicking, no-one is fearful, this is normal for us - it was last year that was a luxury," he said.
Wardman said wine companies would have been bringing in grapes ahead of the expected heavy rain on Wednesday, however he said it did not look as bad as first predicted.
New Zealand Winegrowers chief executive Philip Gregan said winegrowing regions were often hit by rain during harvest, and he was confident the industry could manage.
There was not enough capacity - in terms of processing space at wineries, and the availability of trucks and harvesters - to take in everything at once, so winemakers always made decisions about what to bring in early, he said.
Valley Harvesting director John Sowman said the last few days had been busy for the harvest contracting company. Riper fruit was susceptible to botrytis so anything still on the vines was more at risk of rotting, he said.
Wine companies would probably want to take more fruit in, to avoid disease and the dilution of sugar and flavours from the rain, however they were limited by how much processing capacity they had in the winery, he said.
"If you've got a parcel of fruit that would be best in a couple days' time, it's better to take it in now than it being diluted by the rain."
Climate Consulting climatologist Stu Powell said Wednesday was D-Day for Marlborough in terms of rain. A low would be sitting just north of Golden Bay by Wednesday night, driving heavy rain before it into the region.
Powell said the odds of more rain over the next few weeks, as companies continued taking sauvignon blanc grapes off the vines, was also quite high.
"The sub tropics are spawning lows and depressions all over the place, so there's a good chance we're going to see more cyclonic activity over the next few weeks," he said.
- The Marlborough Express