A major kiwifruit packhouse estimates it could suffer a 10 per cent fruit loss next year after a polar blast damaged some bud-bearing vines.
One grower described Friday's severe frost as "catastrophic" while another, who lost half of their crop, is wondering how to pay contractors the $50,000 owed for work done this season.
Other orchardists had "lost the lot" but the full extent of the damage will not be known for some time yet.
An industry body group said some growers had reported "severe impacts" in the Bay of Plenty and other growing regions following the heavy frost.
Kiwifruit is a $3 billion industry that has faced numerous challenges this year including higher levels of rejected fruit, lower grower returns and a chronic labour shortage.
Trevelyan Pack & Cool managing director James Trevelyan said the frost had destroyed 75 per cent of his own orchard on Brown Rd in Te Puke.
"We have never had frost there before ... there are places I have been surprised it has frosted and others where I think, fair enough."
Trevelyan's, the largest single-site kiwifruit packing operation in New Zealand, was still assessing the cost to its growers and the harvest next year.
"Initially, we thought it may be a 10 per cent fruit loss but it may be higher than that. We are trying to get a handle on it now."
Trevelyan said it was "tough" as the vines were not as floral this year, volumes were down and costs had increased.
"We are a margin-based business and it affects everyone right the way through the whole chain. Obviously, growers are devastated ... everyone feels the pain all the way through."
A Bay of Plenty green kiwifruit grower, who asked not to be named as they were "devastated", said they checked their vines yesterday morning and 50 per cent had been damaged by the frost. They did not have insurance.
"So it's hell if you work for a year then turn around and you'll have no income next year. We are now wondering how we will get through, we just got our winter pruning done last week which leaves you with not much change out of $50,000 on top of other bills.
"We are worried about those big bills that need to be paid and it's affecting our health and stress levels."
That grower knew of another orchardist whose entire orchard was impacted by the frost.
"They have lost the lot."
Pāpāmoa kiwifruit grower Rob Thode said he was up six times during the night last Thursday and into the early hours of Friday tending to his vines to make sure his water systems were working to prevent the frost from taking hold.
That diligence paid off, however he said other growers he was aware of were not so lucky.
He believed a significant volume of the crop had been lost, although he said that would be determined in the coming weeks.
"It was really, really bad. The result for some orchardists who didn't have frost systems in place will be catastrophic, they will lose their whole crop."
New Zealand Kiwifruit Growers Inc chief executive Colin Bond said the extent of the frost damage was diverse with some "unfortunate growers reporting severe impacts while others have none at all, and many in-between".
It had received reports from growers across the Bay of Plenty and in other growing regions.
"Ultimately, the full extent of the damage, in terms of what this means for many individual growers as well as the total volume of fruit produced including the financial ramifications for the industry will not be known for quite some time yet."
Bond said some impacts from frost were immediately identifiable, such as leaves dying.
However other issues may only be noticeable as late as when the fruit matures towards 2023, and reject fruit were consequently found.
Generally speaking, kiwifruit vines in the Bay of Plenty had flower buds on them at the moment, with flowers opening and pollination taking place over the coming weeks, Bond said.
"These flowers will then form the kiwifruit. Vines are especially delicate during pre-flowering and particularly susceptible to damage from frost."
The last similar frost event was in 2002 and there were widespread frosts impacting growing regions. The impact was similar with some orchards heavily hit while others went unscathed.
Private frost insurance was available and Zespri did not have an insurance fund for growers impacted by frost, Bond said.
Zespri chief grower, industry and sustainability officer Carol Ward said it did not offer frost insurance as growers voted to remove this some years ago.
"The recent frost has provided yet another challenge in what's already been a really tough year for the industry. We're continuing to assess the level of damage and our grower teams are working closely with NZKGI to ensure there is pastoral care available for affected growers and to provide information on how to best manage frost-damaged vines."
Michael Franks, chief executive of Seeka - New Zealand's largest kiwifruit grower, told RNZ on Monday the damage it had seen from the frost had come from growers in Katikati, Te Puna, Tauranga, Te Puke, Edgecumbe and Ōpōtiki.
"We were fortunate we had warning, so we had done assessments and brought helicopters in for orchards that didn't have frost protection."
Franks said it would be a while before the full extent of the damage was known and it was doing assessments.
"It's tough for growers because they've just come off a hard season with Covid, weather, labour issues, difficult market returns and quality issues, and of course, they've spent all their money pruning their orchards and getting them tied down, which is a major investment, and now some have effectively lost it".
A Niwa spokesperson said Tauranga averaged about four ground frosts in October, while Rotorua had three. The frost on October 7 was forecast five to seven days in advance.
Minimum temperatures measured in the Bay of Plenty that day ranged from -2.6C in Rotorua to 1.9C in Tauranga, with Te Puke on 0.0C - and ground temperatures would have been 2-4 degrees cooler.
Rotorua, Whakatane and Te Puke all had their second-lowest October temperatures on record. A cold snap of the same magnitude would be highly unlikely this month.
• Growers have a range of measures to mitigate the impact of frost on their orchards.
• Options include portable or fixed heaters, helicopters to circulate warmer air over the vines, or sprinkler systems to form ice over the plant thereby protecting it.
• The most efficient solution might involve more than one system.
- Source: NZKGI
Armed police stood guard as the patched members were led out in handcuffs.