May (No. 496)
Great wines from grafted vines
Nick Dry , Phylloxera & Grape Industry Board of South Australia
What do Cheval Blanc, Corton-Charlemagne and Schloss Johannisberg have in common? Well, apart from being famous vineyards that produce classic wines of their style, they are planted with grafted vines. Yes, that’s right, rootstocks. In Australia we also produce some exceptional, world-class wines but unlike the rest of the world, most of this fruit comes from own-rooted vines. This makes the Australian wine industry the exception to the rule because rootstock use in the rest of the world is necessary to overcome the debilitating effects of phylloxera and is considered normal practice.
Recently PGIBSA conducted ground-truthing surveys in the Barossa, Eden and Clare Valleys. In my role as rootstock project manager it was a good opportunity for me to talk to growers and answer any questions about rootstocks and the benefits that they offer. However, it was somewhat disheartening to hear many of the growers state that, while they had thought of using rootstocks for their new plantings, they were put off by reports that it was not possible to produce premium fruit with rootstocks. These views were echoed in the Phylloxera Board’s Annual Grower Survey; when growers were asked why they would not consider using rootstocks, the majority of the comments were along the lines that “it is not possible to produce premium-grade fruit (on rootstocks)”.
It is a major aim of PGIBSA’s current rootstock project to address these opinions and the early results look promising. While we wait for the full results, I can provide an example which might help to sway the opinions of those who believe that it is not possible to produce premium fruit from vines grafted to rootstocks.
I recently downloaded two lists of wines: one was Langtons Classification of Australian Wine III and the other Wine Spectator’s Top 100 wines for 2004. I was interested to see how many wines from each of these lists came from grafted vines. In Langton’s Classification, of the 100 wines on the list I could only identify one that is produced completely from grafted vines. This would not come as a surprise to many and will confirm the opinions expressed by many in the Australian wine industry. However, looking through Wine Spectator’s Top 100 provides a different perspective. It was interesting to note that 88 of the top 100 wines from around the world come from regions where the presence of phylloxera necessitates the use of rootstocks. What these examples clearly demonstrate is that while the best wines in Australia are currently being produced from own-rooted vines, the very best wines in the world come from vines grafted to rootstocks.
The continued assertion within the Australian wine industry that rootstocks have a negative influence on winegrape quality will, in the short term, limit the ability of the Australian wine industry to become more efficient producers, and in the long term it could severely affect the wine industry’s ability to recover from a wide-spread outbreak of phylloxera.
Nick Dry is the rootstock project manager for The Phylloxera & Grape Industry Board of South Australia. He can be contacted on (08) 8362 0488.