Combining a love of research and grapes has led Cath Kidman to doing great things with new technology that could benefit the entire industry – and those beyond.
Cath Kidman grew up in the Yarra Valley and was captivated by viticulture while studying at La Trobe University and working part-time at T’Gallant with the charismatic Kathleen Quealy. An honours degree at La Trobe and later a PhD at the University of Adelaide, where she won the Dean’s commendation for doctoral thesis excellence in 2014, convinced her she was an academic. But time spent working in the vineyards at Wynns under the big skies of Coonawarra with Allen Jenkins and senior winemaker Sue Hodder taught her that to have any meaning, the research needed a practical output.
A close look at her work on Johnson’s Block shows how detailed viticultural investigation can have a significant impact on wine quality. When shiraz needs water, it shows distress by losing its leaves, yet responds quickly to irrigation and becomes a picture of health once more. Cabernet, on the other hand, doesn’t provide visual clues when it needs water nor when it has enough.
Kidman’s research looks for the razor-sharp, fine line between stressing the cabernet and not giving it too much water. She wants the vines to produce grapes that are concentrated in colour and flavour, and she is looking for the judicious management of water to achieve this. Her research includes the use of thermography with an infrared camera in the vineyard, producing a heat map. Changes in colour show the point at which the cabernet vines need no more water.
“I love using new techniques and new technology to better understand and evaluate how cabernet is performing.”
“As a wannabe-academic, I love using new techniques and new technology to better understand and evaluate how cabernet is performing,” says Kidman. “In this case, saving the precious resource of water by not feeding the vines more than they need is a significant bonus.”
While this work with thermography is just at the research stage with Adelaide University, it is on track to become widely available and will likely benefit industries other than viticulture.
One of the ways that Kidman keeps in touch with her heritage vineyards is to walk the vines three or four times a year; she places a cattle tag on those doing particularly well, so that she can take cuttings from them for propagation.
In 2016, the cabernet on the unirrigated Johnson’s Block was looking in terrible condition after the hottest vintage on record. However, when Kidman walked the vines she occasionally came across a vine that looked awesome with fresh, green leaves, and bunches in great shape. She tagged these superior, heat-resistant vines, which she saw as having learnt to adapt best to extreme heat during their 60-year lifespan. The fruit from these 48 vines was harvested separately, and produced outstanding wine with beautiful colour and bright, ripe tannins. The next stage of the process was to cull all but the very best vines. Those on deep soil were considered to have an unfair advantage and so the number was reduced to 18. Testing for virus and other imperfections reduced the number to nine superior clones that were considered to use water more efficiently than the others. A commercial clone (SA125), which is widely planted in Coonawarra, was added to the trial as a control.
Of these clones, 110 cuttings have been propagated in a new vineyard, a little under a hectare, south of the original block, and known affectionately as ‘Baby Johnson’. Her research seeks to answer whether the drought superior capability that these vines have learned over 60 years can be passed on to the daughter vines. Perhaps these cuttings will outperform commercial clones or even the Wynns heritage clones.
Kidman is excited because she sees this as a way to retain and evolve cabernet rather than look for alternative varieties. In looking at this vineyard, she wonders if it is putting us in a better position to handle an environment that is hotter and one in which we need to be more conscious about water conservation.
As our Viticulturist of the Year for 2020, we salute Cath Kidman’s meticulous research and the ways in which it impacts on the wine quality at Wynns in the short and the long term. It’s valuable and impressive in itself, but even more important when considered as part of the contribution that the team of viticulturists makes to the quality of wine at Wynns.
Photography courtesy of Wynns.