Christine Webster, Murray Pioneer

Heatwave conditions at the start of the 2026 Riverland vintage, followed by recent heavy rainfall in some parts of the region, are causing headaches for many wine grape growers.

The Oxford Landing Winery’s regional viticulturist Glynn Muster said the long spell of hot weather in late January and February had initially caused heat stress to some vineyards.

“We had an extremely hot and dry February and January, and I believe recorded the hottest day ever in the Riverland,” he said.

According to the Bureau of Meteorology on January 27, Renmark recorded its hottest day on record reaching 49.6C and Loxton also experienced its hottest day ever with a temperature of 48.2C.

Glynn said the hot dry heat towards the end of summer meant irrigation had to be increased at vineyards throughout the region.

“The heat and water stress has impacted on the yield of some properties,” he said.

“Some growers have found it really tough, and on their properties experienced a 30 per cent decrease in average yield.”

The Oxford Landing Winery sources winegrapes from growers across the Riverland and has its own vineyard at Qualco, northwest of Waikerie.

The company’s winery is based at Nuriootpa, in the Barossa Valley.

Long-anticipated rain finally arrived on February 28, and March 1, with some primary producers in parts of the Riverland experiencing their highest rainfall in two or three years.

Glynn said the Riverland West area received less rainfall than other parts of the region such as Kingston-on-Murray, Moorook and New Residence.

He said vineyards at Blanchetown, Waikerie, and Qualco received about 30 to 50mm of rain, and the more eastern parts of the Riverland received higher rainfall of up to 120mm.

Glynn said some vineyards experienced flooding after the rain on February 28 and March 1, causing some delays to their vintage.

“You possibly may be unable to access these vineyards for about a week,” he said.

Glynn said some rain also fell in the region on January 22.

He said if further rain events occurred over the next couple of weeks, fungal diseases such as botrytis and sour rot could also start developing among vines.

Glynn said in some parts of the region that received about 170mm of rain from late February 21 to March 1, signs of botrytis had already begun appearing on grapes.

He said the best way to prevent fungal diseases such as botrytis from occurring was to trim and hedge the impacted vines and lift the canopies off the ground, to enable the bunches of grapes to dry out.

Glynn said it had been an unusual year for Riverland viticulturists with so many variations in weather and crop yields.

He said at Oxford Landing’s own vineyard at Qualco, areas of the property impacted by frost last vintage had produced above-average and record yields this year.

Glynn said the September 2024 frost event had resulted in a massive wine grape yield reduction for last year’s vintage.

“There were certain parts of the vineyard we did not harvest because it had experienced a 100 per cent crop loss,” he said.

“Because they didn’t have a crop load last year, the stress on these vines weren’t great because they weren’t carrying a crop and then this year, they really produced an amazing yield.

This article appeared in Murray Pioneer, 11 March 2026.