Led by chief viticulturist Nigel Blieschke, Torbreck Vintners has gone through a major overhaul of its vineyards since 2016, and the results are paying off.

When Nigel Blieschke first arrived at Torbreck Vintners in 2015, he was greeted with an array of problems. Dilapidated vineyards, worn out and ageing irrigation, rampant Eutypa dieback and weeds aplenty were all immediately added to the 'to fix' list. While Nigel admits the list seemed daunting at times, he knew he had the skills to get the vineyards not only back on track, but better than they had ever been before, with sustainability always at front of mind.

Snapshot

Farm/Enterprise Name: Torbreck Vinters

Farm/Enterprise Location: Barossa Valley, South Australia. Specifically Marananga, Gomersal and Lyndoch.

Type of Enterprise: Viticulture (vineyards and cellar door)

Primary Markets Served: Australian domestic, UK, USA. Exports to 52 countries.

Staffing: 30

Property Size: 130ha (86ha owned, 44ha leased/managed)

Average Annual Rainfall: Ranges from 520mm to 650mm

Climate: Mediterranean climate (cool wet winters, warm dry summers)

Soil Types: Highly varied - sand, clay, red brown earth

Website: www.torbreck.com

Farm vision

Torbreck cellar door in Marananga, South Australia

With an unwavering commitment to continuous improvement, Torbreck Vintners is dedicated to producing premium wine which remains highly sought-after Australia-wide and internationally. Meticulous thought is put into the entire process, from the vineyards right through to the bottle.

Torbreck strives to constantly improve productivity and profitability in the vineyard, ensuring their environmental footprint does not suffer in the process. Their tweaks to viticultural practices rarely have just one benefit, with a multitude of advantages usually occurring. By maintaining and boosting soil health, chief viticulturist Nigel Blieschke believes Torbreck is well-placed to face whatever Mother Nature throws - or doesn't throw - its way.

Farm history

Nigel Blieschke is chief viticulturist at Torbreck

Torbreck Vintners was established in 1994 and is situated in Marananga, on the western end of the Barossa Valley. Starting with just a handful of vineyards, investment throughout the 2000s has seen Torbreck grow to manage 11 vineyards across Lyndoch, Marananga and Gomersal, all in the Barossa. Torbreck specialises in shiraz, grenache and mataro, yet has steadily increased its offering in recent years.

Originally founded by David Powell, Torbreck is now owned by Peter Kight, who owns Quivira Winery in Sonoma County's Dry Creek Valley in California. Torbreck is led with expertise by two widely respected members of the wine industry, chief viticulturist Nigel Blieschke and chief winemaker Ian Hongell, who began at Torbreck in 2015 and 2017 respectively.

Challenge: Tackling soil variability

Soil Health / Testing & Analysis

When Nigel first arrived at Torbreck in 2015, he was on a mission to get the run-down vineyards up to scratch; however, huge variability in the soil put a spanner in the works. This variability was caused by a number of factors, including differing microclimates across the company's vineyards, and a lack of irrigation on some blocks, which had led to a deterioration in soil health.

'Every metre is different, the difference in soil structure is amazing,' Nigel says.

One vineyard in particular - the Descendant vineyard, in Marananga - was particularly challenging, thanks to old geology in the area and subsequent folding and faulting resulting in huge horizontal variation in soils across the landscape.

Solution: Understand, then mulch

Before tackling soil variability, Nigel first had to understand the specifics of the variation. Before Nigel joined Torbreck, soil testing had been limited to a few soil surveys when the vineyards were first planted, and some basic chemistry tests. In 2016, Nigel organised an aerial survey to gather NDVI (normalised difference vegetation index) information on all the vineyards, which informed him of the areas which were lacking vegetative vigour, and areas which were doing well.

Using NDVI information as a guide, Nigel used Australian Precision Ag Laboratory (APAL) testing to analyse the chemical properties of two to three soil samples in each vineyard. Nigel chose samples from the least vigorous and most vigorous parts of each vineyard, as well as a third sample which represented the majority, in instances where there was a large area of similar vigour. Having collected GPS information for each of these samples, he went back to the same areas and conducted a biological test of the topsoil.

The APAL tests showed the best-structured soils had higher calcium, while the worst-structured soils had high potassium and magnesium relative to calcium. The biological testing fell hand-in-hand with the APAL results.

'Where there was good structure, there was good life, and the best vineyards were ones with large areas of good structure, high calcium and good biological activity.' Nigel says.

Once he understood the specifics of the variability, Nigel was able to develop an action plan as to how to improve the soil health in problematic areas, while maintaining good health in the better areas.

'People wanted to manage everything the same way, but I didn't want to, because everything was so different,' Nigel says.

To boost soil health, Nigel applied compost, gypsum (in areas with weak sodic clays) and then a woody mulch. All applications were variable rate, with less-problematic areas receiving less mulch. Mulch is applied following vintage (in autumn), to allow for winter rains to help the mulch to 'settle down'.

The applications have not been one-offs. Since 2016, over 9,000 cubic metres of mulch has been applied to Torbreck vineyards, with another application just around the corner.

'What I've learned with soil health is you cannot stop, it is a constant effort to keep things as they should be,' Nigel says.

Outcome: Yield and quality boost

Nearly a decade of consistent effort into fixing 'weak spots' and boosting soil health has translated into an increase in both the quality and yield of grapes grown at Torbreck.

'In 2017 we had a few issues with bud mite, but in 2018 we increased yields by 100 per cent in some blocks, in 2019 we got frosted, and in 2020 we had all the flowers blown off with a hot northerly wind. Last year was our most successful year, we went from producing 350 tonnes in 2021 to 439 tonnes in 2022 with a similar environmental footprint, but it has taken us eight years to get there,' Nigel says.

Challenge: Eliminating weeds... for good

Pest & Disease Management / Sheep / Time-Controlled Grazing

Hillside vineyard is one of Torbreck's most southern vineyards, located in Lyndoch. A piece of Barossa history with some shiraz plantings dating back to 1850, the vineyard was full of weeds, including asparagus, couch grass, milkwood, olives and artichokes, when Nigel first joined Torbreck. The abundance of weeds on the block took valuable resources away from the vines, which proved particularly problematic in dry years.

Solution: Grazing inter-rows

To keep the weed count down they established a management system centred around strategic inter-row pasture growth and subsequent grazing.

Fixing the weed problem at Hillside was a two-step process: eliminating the existing weeds and then implementing management techniques to ensure weeds stay out of the picture.

While Torbreck tries to avoid the use of herbicides, fungicides and inorganic fertilisers, elimination of the existing weeds required repeat applications of Roundup to the vineyard and areas which were soon to be vineyard.

To keep the weed count down they established a management system centred around strategic inter-row pasture growth and subsequent grazing. In 2017, Nigel sowed the inter-rows of Hillside with a mixed-species pasture mix containing clovers, medics and ryegrass, which naturally regenerate. All species chosen were varieties which would not outcompete the vines in dry years, and which would make good sheep feed. Nigel then brought in sheep from a local property to graze the inter-rows during winter. With weeds outcompeted by the pasture mix, and sheep grazing the pasture and helping to clean up any summer weeds, not only were weed counts reduced, but there was no longer a need for cultivation of the inter-rows - reducing time, labour and diesel requirements.

In terms of sheep stocking rate in the inter-rows, Nigel said he introduced 'as many sheep as possible', moving them off when they had run out of fresh feed, which generally occurred in spring. When the sheep are removed from the inter-rows, they are moved onto a previously bare area of the Hillside property with a Blanchetown Clay soil. Soil tests of the Blanchetown Clay revealed high boron content and the area had very poor drainage, making it unsuitable for planting vines yet good for growing dryland lucerne. Nigel sowed the paddock to dryland lucerne and fenced it off, with the sheep grazing the paddock all through the dry summer months.

Outcome: Weeds are under control

The pasture growth and grazing system has been a very effective method of controlling weeds in the Hillside property, with a number of additional benefits. In the first year of employing the system, Nigel eliminated the need for cultivation, and reduced the need for tractor passes, leading to an overall 50 per cent drop in diesel use. Soil health has also been boosted by the inclusion of pasture species in the inter-rows. The Hillside property is now thriving, with Nigel having planted an extra 26 hectares of vines across the property.

The grazing method has been valuable and successful to the point that sheep now graze four of Torbreck's 11 vineyards, in an effort to reap the same multitude of benefits seen at the Hillside property.

Challenge: Getting on top of disease

Pest & Disease Management
Good pruning leads to consistent growth. Today, disease at Torbreck is not nearly as much of a problem and yields have become less variable.

Eutypa dieback is a disease plaguing many vineyards around the world, and Nigel found the Torbreck vineyards to be no exception. The 20-hectare Descendant vineyard was suffering particularly badly.

'The vineyard was planted in the late 1990s, and 20 years after planting is generally when Eutypa starts to show up,' Nigel says. 'It was everywhere, it was going nuts, and it was really messing up yields and quality.'

Solution: Refining pruning methods

Nigel knew a lack of irrigation in a number of the Torbreck vineyards was contributing to the disease prevalence and went about fixing the valves and automating the irrigation system where needed.

'The business focuses on a lot of dry growing, rather than high input viticulture. Disease was prevalent and getting worse in a lot of our young vineyards, because we were running them pretty lean.'

He also invested a lot of time and effort into improving pruning strategies, in an effort to combat disease.

'Pruning is one of the most important jobs a viticulturist does, but as profitability comes down, people throw the pruning out the window, they can't afford to prune properly,' Nigel says.

To refine the pruning methodology, Nigel met with some Italian consultants who trained him in how to prune properly for the sake of vine physiology, and reducing disease risk.

'When you make big cuts, you open the vine up, that is what had happened in these vineyards and what had led to Eutypa becoming really bad,' Nigel says.

He is now trying to eliminate cutting anything older than first or second-year wood, as big cuts to old wood is what allows Eutypa into the vine.

Outcome: Effective and efficient

With good pruning leading to good and consistent growth, Nigel said disease is not nearly as much of a problem these days, and yields are also less variable.

Thanks to the Italian consultants also training five contractors Nigel uses to help with vineyard maintenance, better pruning practices are carried out across all of Torbreck's vineyards. The five contractors pruned 144,000 vines last year using the refined methods and completed the pruning quicker than they had the previous year.

'The team are Cambodian, and they are fantastic - they do all my pruning, training, thinning and harvesting. I give them work for eight to nine months every year, and they are passionate about working here. I am very proud that I have built a team who are well-trained, effective and who want to work for us,' Nigel says.

Future plans

Nigel is proud of the work he has carried out to date, with the improvements having already led to tangible results in a relatively short timeframe. He is looking forward to continuing to refine Torbreck's viticultural processes in the future, for better sustainability, productivity and profitability of the vineyards.

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