Industry looking ahead

New varieties and trellis systems in the spotlight

It was one of the most challenging dried grape seasons in recent times, and one of the lowest crop yields in years.

The 2023 season – plagued by wet weather and downy mildew – yielded about 7500 tonnes, about half of the forecast for the season.

The Dried Fruits Australia Innovation Committee met post-harvest to discuss the season, its challenges and ways the industry can recover and prosper.

Led by grower Ashley Johnstone, the Innovation Committee last year took on a major project to have a specific dried grape harvester designed and developed to help relieve a bottleneck at harvest time.

This year, the group is looking to address both long and short-term issues.

Following the Innovation Committee’s meeting in June, Ashley said the group had this year decided on several key areas to focus on: varieties, trellis systems and dehydration.

Varieties

Developing high-yielding earlier varieties is a key priority for the industry.

The hope is to have a variety that will mature earlier and produce a high yield, providing a higher probability of lighter coloured fruit and achieve drier fruit on the trellis.

“One thing that has happened in the past two seasons is we've seen a varietal shift from sultana being the predominant variety in the industry to sunmuscat,” Ashley said.

“There’s been all this good work done with development, however it is a later variety, so we’re seeing potential problems with more moist fruit having to be harvested from the trellis just simply because we’ve got more late varieties in the ground.”

An event will be held for those who hold the genetic material –SNFL Group (Sheehan Genetics), Sun World and CSIRO – to share information with growers and interested industry parties about the varieties in development.

Ashley said several potential varieties for the dried grape industry had been developed.

“DFA has signed a testing agreement with Sheehan to test another four varieties, so we’re in that testing variety process,” he said.

“Rather than having a testing license agreement with an individual, you have it with DFA, then you can spread that license across a number of growers. And DFA absorbs that cost, not the grower.”

Ashley said it was important to continually work on new varieties because there were multiple steps and several years before the new varieties would be in production.

Trellis design

The Innovation Committee has prioritised producing a guideline on what trellis systems are available in dried grape production.

Ashley said while Shaw swingarm trellis had been regarded as the best practice trellis for the industry, there were other dried grape trellis systems in use.

“Swingarm does have issues, particularly with larger corporate growers who don’t really like it because of the tipping process,” he said.

“There are existing growers who are achieving good yield on alternate trellis systems and it's worthwhile investigating these systems to see if they’re suitable for anyone else.”

The project will develop a guide, with imagery or sketches, to outline a description of each trellis system and the steps in its operation.

“They’re all pruned differently and they’ve got different harvest requirements,” Ashley said, highlighting the requirement of swingarm trellis to use a specific type of harvester that’s not as readily available as winegrape harvesters.

“If you’re a winegrape grower who’s feeling the pinch in the winegrape industry and you want to look into dried fruit and you’ve got harvesting equipment you might look at some of these alternative systems that might work quite adequately for your situation,” Ashley said.

“It’s really to give people as much information as possible so they can make an informed decision.”

He said the guides would be aimed at those looking to invest, or re-invest, in the industry and to give them a clear idea of what options they had.

He hoped the guide would also include a study into the viability and costs associated with retrofitting or changing an existing system from one to another.

Dehydration

The industry will explore ways to improve the dehydration process in dried grape production.

The current method of gas dehydration has been in use in the industry –without update – for some time.

The committee is keen to find ways of dehydrating fruit in a more efficient and cost-effective way.

Ashley said another issue was that while some growers dehydrated their own fruit, others didn’t, leaving the job of dehydration to processors, which could create added pressure as yields increase, particularly from larger scale growers.

Events

Supported by the Dried Grape Production Innovation and Adoption Program, events continue to share information to advance the industry.

A recent field walk at Ashley Johnstone’s block highlighted two different mechanical pruning machines.

It was particularly helpful to see the results of last year’s pruning using the mechanical pruners, and to see the vines had produced good canes.

Another event will highlight varieties that are on the way for the industry, presenting opportunities for growers to produce high yields earlier in the season.

Ashley said the Innovation Committee was focused on finding ways to minimise costs and increase yields.

“And you can’t do that if you stand still – you’ve got to continue to look forward.”v