Canberra winemakers were reeling from the heavy frost overnight on Thursday, Canberra’s coldest October morning on record, which wiped millions of dollars from the industry.

As they assessed damage from their vineyards during the day, some reported losses of 70 per cent or even higher from low-lying vineyards.

Ken Helm has four vineyards at Murrumbateman. Two were devastated, with crop damage of 80 per cent or more, amounting to total loss, he says. Another of the vineyards lost 50 per cent of the crop, and a fourth was untouched.

At Clonakilla, Canberra’s flagship vineyard, owner and winemaker Tim Kirk estimated at least 50 per cent loss, and possibly up to 60 or 70 per cent, with low-lying vineyards the worst hit.

Advertisement “The heart and soul of the business comes from the estate vines,” he said, referring to the shiraz viognier for which the winery is so well known.

“And that’s where it really hurts the most, to see the shiraz vines wilting and turning brown.”

The temperature at Canberra Airport fell to minus 3.4 degrees about 6am on Friday, eclipsing the previous October record of minus 3.3 degrees, in 1957. Weather stations at Braidwood and Goulburn both registered minus 5 degree temperatures about dawn.

Meteorologist Ben McBurney from Fairfax-owned Weatherzone said the freezing start in Canberra was in complete contrast to the fiery conditions just 200 kilometres to the north.

“It’s an amazing contrast - such conflicting air masses ahead of the trough. Before we had a very, very hot air mass, a dry air mass, and that dry air stuck around as well, and the cold front behind that was full of very cold air,” he said.

It was the worst frost damage in the vineyards since November 2007, and while Kirk said it was difficult to put a financial number on the loss, it would be more than $1 million.

At Eden Road, Nick Spencer said he, like others, was feeling “a bit sombre”. He estimated he would lose about half the crop on his Murrumbateman vineyard, but because he makes wine from Tumbarumba and elsewhere, he was cushioned from the worst of the impact.

“For us it’s bad, but from a financial point of view, we only rely on a small amount of fruit from our vineyard that goes into our estate shiraz, and it’s not financially that significant,” he said.

“But I feel very sorry for some of my kin that have had millions and millions of dollars wiped out overnight.”

Ken Helm said big frosts hit seven to 10 years, the last in 2007 and before that in 1999.

“It’s something which I expect every now and then,” he said. “I feel for the people who haven’t been in the industry as long as me, they will be devastated because they haven’t seen something like this before.”

Kirk, too, was philosophical.

“This is part of growing grapes and making wine in Canberra. This is part of that great drama that you’re going to have seasons where you suffer significantly from frost damage. It makes a mess of things, but we’ve seen it before and we’ll recover from it.”

The 2013 vintage now seemed “an even greater blessing”, Kirk said.

“The winery is full of very, very good wine, so that will certainly soften the blow.”

The warm winter meant bud burst came three weeks earlier than usual this year. For shiraz, bud burst came in mid-September, leaving the vines vulnerable to frosts. Winemakers have been alert to the risk, and Spencer said he was keeping the grass low between vine rows to encourage air flow.

There had been four frosts since bud burst this year, but the difference on Thursday night was the longevity of the below-zero temperatures, he said. It got cold quickly and stayed that way for some hours through the night.

“It was marginally colder than the other frosts, but we think it was the longevity that really caused all the problems,” Spencer said.

“With an event like last night where there was minus three or minus four up at about two metres above the ground, there’s not much you can really do.”

The full extent of the damage would only become clear in the hours and days following the frost.

“It’s kind of like pulling broccoli out of the freezer as it warms up all the cells start bursting so as they start growing again after the frost you can see where they’ve died,” he says.

Bryan Martin makes wine at Clonakilla and also has his own nearby vineyard, Ravensworth. He said damage was such at his own vineyard that he hadn’t been able to face a close assessment of it yesterday, given all his vines were low-lying and likely to have been hit very hard.

“By Sunday morning the bits that are dead from being frozen will fall off,” he says. “They’ll look like rotten vegetables.”

After the big frost of November 2007, it was too late for a second crop, but this year vines have the chance to grow new buds, giving rise to the possibility of a second, much later crop. But it might struggle to ripen, and would be much smaller.

“Each shoot produces 300 or 400 grams of fruit and two bunches,” Martin says. “But the second shoot will only produce one small bunch.”

“Everyone’s a bit deflated,” he said, “because it was looking good.”

At Four Winds, also in Murrumbateman, Sarah Collingwood confirmed they had also sustained damage from the frost, but she did not want to say how much.

But vineyards in other parts of the district escaped the worst.

The overnight temperature at Brian Schmidt’s Sutton vineyard was 1.6 degrees.

But Schmidt said the combination of hot and cold weather this spring had left the vines “a bit of a mess”.

“Some are advanced and some barely have a leaf out,” he said.

At Lake George, Lerida winemaker Jim Lumbers said they escaped the frost altogether, just had they had during previous devastating events.

And at Hall, Alex McKay was working in a vineyard yesterday that was unscathed.