Spring has sprung at Ata Rangi vineyard in Martinborough. PHOTO/PETE MONK
Following severe frosts which damaged crops last year, GIANINA SCHWANECKE talks to winegrowers around the region about their frost fighting efforts this spring.
Te Hera Estate – Martinborough
Te Hera Estate, just outside of Martinborough, was one of the vineyards hit hardest by severe frosts last year.
This spring has been no less challenging for owner John Douglas who has spent the last few weeks fighting frost with fire.
In 2018 he lost up to 70 per cent of his usual grape yield.
“Normally, I have between 40-50 barrels of wine. Last year I got 13 barrels,” he said.
He was not alone in that loss and has spent many recent nights anxiously awaiting frost warnings.
Situated a few kilometres outside of the Martinborough township, about six kilometres down Te Muna Rd, it often gets slightly cooler, slightly earlier at his vineyard than closer to town.
Though he has frost fighting machines, they rely on inversion — a warmer layer of air over a colder layer of air.
“It just got too cold for the frost fighting machines,” he said.
Still, Douglas would rather rely on them then having to predict when a helicopter might be needed and battling to book it out.
“That’s one of the joys of using a windmill instead of a helicopter. It’s a really useful piece of equipment to have.”
There are a few anxious nights left for him though as he waits for warmer weather to arrive.
Ata Rangi – Martinborough
Gerry Rotman has been working at Ata Rangi in Martinborough for close to 15 years.
Every spring is the same for the vineyard manager as he prepares to fire up the wind machines.
He said the frost this year had been “unrelenting”, occurring two or three times a week for a little under a month.
Though tired, he was also optimistic and there had been little damage so far.
“We’ve been doing pretty well so far this year,” he said.
“We’re pretty well covered with wind machines, except for one block where we use a helicopter which we share with the next-door neighbours.”
Last year they lost about 40 per cent of their yield due to the severe frosts but this year the buds were coming through slightly later.
“At the moment we’ve got marvellous growing conditions,” he said, praising the rain which was falling as we spoke.
Johner Estate – Gladstone
Gladstone’s Johner Estate was also hard hit by frost last year.
Assistant winemaker Uttam Floray said the vineyard lost between 30 to 40 per cent of its usual yield.
It was the severity and intensity of the frost which had hit hardest, he said.
“Last year was really bad.
“We are not out of the woods yet either this year, though the weather is looking great at the moment.”
The vine buds were maturing slightly later this year and were about two weeks behind by Floray’s estimates.
Four weeks ago, when temperatures first plunged to below zero degrees, the buds still hadn’t opened up which meant they hadn’t been badly damaged.
“That was quite crucial for us,” he said.
“It’s about timing and where the buds are.”
Still, the team was busy battling frost most night
“We are always anticipating the worst.
“There was a real brunt of frost the last few weeks, especially last weekend and the weekend before.”
The vineyard runs diesel powered frost fans to draw down the warmer air in the inversion layer and blow it through the vines.
They also have portable frost machines to reach the furthest section of the recently expanded vineyard.
At the Lansdowne vineyard in Masterton which they lease, they use sprinklers to prevent frost damage.
“That’s the safest way to deal with frost,” he said.
Gladstone Vineyard – Gladstone
Over the road, it’s been a busy few weeks for David Jackson, vineyard manager at Gladstone Vineyard.
“The team has done a great job managing the last few weeks. We are very much on the watch for frost,” he said.
“It’s always a nervous time of year.”
He estimated they lost about 20 per cent of the usual yield due to last year’s severe frosts.
“That frost event last year really affected us. We will see an effect on this year’s yield too.”
The vineyard primarily used frost fans though a spray system was in place in one section of the vineyard.
“On those really cold nights we also use frost pots sometimes,” he said.
This year hadn’t been too bad though and there was less damage as the buds were slower to open in Gladstone, Jackson said.
“In Gladstone we are slightly behind in terms of bud bursts compared to Martinborough growers.
Matahiwi Estate – Masterton
It was a different story for Karina Southey, Matahiwi Estate’s vineyard manager in Masterton.
She said the vineyard wasn’t been affected at all by last year’s frosts and they used helicopters as frost protection.
“Over the past month we have had a few frosts, but the vines are looking great and growing beautifully.
“We keeping our fingers crossed there will be no more frosts this year,” she said.
Frost Watch
There would be some relief for growers this week though as Metservice meteorologist Kyle Lee said temperatures were above average for this time of year due to warm and humid air over the region this week.
Nest week would see temperatures cool once again, however.
“From next week the temperatures are set to cool once again to below average which could mean the chances of temperatures dipping below 4C mark and frosts although unlikely remain a possibility.
“This below average temperature trend continues for the first week of November but by this stage the average minimum is high enough that frosts will probably be unlikely.”