Lessons learnt during vintage 2013

Vintage 2013 was marked by hot spells and low rainfall in many regions of Australia, contrasting widely with the unrelenting rain that growers faced in 2010–11. As the vintage draws to a close, AWRI Senior Viticulturist Marcel Essling and colleague Matt Holdstock, AWRI Senior Oenologist, share what they believe are the key lessons for producers from the recent vintage.

Key lessons from the vineyard

Seasonal variability: ‘Getting to grips with what the weather is going to bring each vintage is tricky, but there are resources provided by the Bureau of Meteorology than can give growers a head start’, Marcel Essling said. These include seasonal outlooks for both temperature and rainfall. Growers are advised to be prepared to respond to the season and adjust management practices accordingly. As Marcel highlighted, ‘low winter rainfall this year signalled a need to start irrigating early’.

Heatwaves: During January, much of Australia faced long stretches of warm weather; the longest on record in some parts.

‘Managing vines during heatwaves through appropriate use of irrigation and limiting bunch exposure is critical to vine health and final grape quality’, Marcel said.

Carbohydrate reserves:  ‘Temperatures above 38°C, dry soils or strong winds will shut down photosynthesis’, Marcel said, explaining that this will slow down ripening and have an effect on carbohydrate reserves that the vine needs the following season. Post-harvest management that maintains a healthy canopy into autumn is essential.

Smoke taint: Regions in Tasmania and north-eastern Victoria were affected by bushfires in early 2013. The eventual effect on fruit quality depends on the intensity and duration of smoke, as well as the vine’s growth stage at the time of the smoke event.

‘Strategies for avoiding smoke taint in the vineyard are limited, but growers should be aware of the risk’, Marcel said.

Condensed intake: This vintage was one of those years when a lot of fruit was ripe at the same time. For growers selling to wineries at full capacity, this can mean delays in harvesting.

‘Keep your buyer informed about the progress of your fruit in the lead up to harvest to help smooth the process’, Marcel suggested.

Low disease risk: ‘A dry year means less disease pressure and this should be seen as an opportunity to save money on agrochemicals, so be flexible in your spray regime’, Marcel said.

Much to learn from vintage 2013 in the winery, too

Compressed vintage: Vintage 2013 got underway early, marked by hot days and warm nights around the country, which led to grape sugars increasing rapidly, resulting in a compressed vintage. As Matt Holdstock explained, the need to vinify both white and red grapes that ripened at the same time caused some logistical challenges including a shortage of tank space for fermentations or settling, competition for winery presses and higher grape sugar levels due to harvest delays.

Fermentation challenges: The large amount of fruit arriving on wineries’ doorsteps all at once meant winemakers had to free up tank space quickly for fermentation, making avoiding stuck fermentations or other delays even more critical this year. As a result, the AWRI published an eBulletin amidst the compressed vintage to remind winemakers of the critical steps than can be taken to avoid fermentation problems.

Technical advice: The AWRI on average receives 70–100 calls per month relating to technical issues in wine production.

‘About 20–25 percent of those calls require investigation – an in-depth look at the problem through analysis, rather than simply discussing the matter with the producer.

‘This vintage was a good one from a grape and wine quality point-of-view, apart from the typical challenges wineries face during vintage. The top three issues we fielded calls on this vintage were:  hazes and deposits in wines, taints and contaminations, and managing smoke taint. The AWRI also assisted with vineyard to winery contamination problems and issues relating to matter-other-than-grapes, but nothing unusual in terms of microbial spoilage-related matters’, Matt said.

The AWRI’s Winemaking Services team can be contacted on 08 8313 6600 or winemakingservices@awri.com.auFor more information, contact Adrian Loschiavo, GWRDC Program Manager, adrian@gwrdc.com.au