There’s a hammock chair on the balcony at BioWeingut Karl Renner with staggeringly beautiful views of Steiermark (Styria), rightly described as the “green heart of Austria”. The balcony, above the winery and near the kitchen of the family home, looks like a wonderful place to relax. Karl Renner, who took over the family wine business in 1997, comes here to think but he finds it difficult to relax. All he sees is the work that needs doing in the family’s organically-farmed vineyards.
BioWeingut Karl Renner has 6.5ha of vines, including about 0.9ha of rented vineyards and 1.8ha of new-generation piwi grape varieties. The piwis cause much less stress than his other white varieties (Sauvignon Blanc, Pinot Blanc, Morillon (Chardonnay), Muskateller, and Welschriesling).
In this “challenging vintage” – where there was much more disease pressure – he only sprayed the piwi vines once, with copper and sulphur, at the end of June, beginning of July to prevent the fungus attacking older leaves. For one application on the piwis he used 1kg of Bordeaux mixture per hectare whereas for the conventional varieties he used 4kg.
Karl knows it’s been a tough year for the vines as he’s spotted some fungal diseases on two of the mildew-resistant piwis, Souvignier Gris and Chardonel. “This says the pressure was very high,” Karl states. For the first time, he may have lost 10% of these grapes to rot but he describes their performance in general as “super, wonderful”.