Last year, a bottle of 2002 Domaine de la Romanee Conti sold in Australia for $11,500. This rare and beautiful wine, from one of the world’s great wine producers, has been certified organic since 1985, which is how it would have been produced for most of the almost 500 years that grapes had been grown in that vineyard.

That is the truth of organic and biodynamic wines; they are made simply, and simply made, the way wine was made for hundreds, if not thousands, of years before what Mark Davidson of Tamburlaine calls “chemical farming” (AKA conventional farming) became the norm.

But chemicals do figure large in conventional grape growing and winemaking: in the vineyard, in the winery and, finally, in the bottle. Let’s begin in the vineyard.

Chemicals in the vineyard

The Australian Wine Research Institute (AWRI) lists well over 100 “Agrochemicals registered for use in Australian Viticulture”. Conventional winemakers use varying numbers and amounts of those on the AWRI list to kill weeds and insects and to deal with mites and moths, scale and mildew and fungus infections.

Organic and biodynamic winemakers try to use as few interventions in the vineyard as possible, with 99 per cent of the AWRI list banned from use by them. Indeed their certification (see below) strictly limits inputs from very few to (with biodynamic certification) none at all. If a certified grape grower is found using any forbidden chemical or additive, they will lose their certification and their right to call themselves organic or biodynamic growers.

Mark Davidson began making wine in the Hunter Valley 25 years ago. “When I started,” he says, “chemical farming was booming. There were more and more chemical inputs every season. I was technically trained in that sort of farming from my uni days. And, because this was my ongoing farm management experience, it gave me the opportunity to see the cause and effect and come up with some opinions as to whether it was sustainable or not. About 15 years ago, I decided organic was the way to go. For me, it emerged as a far better management system for better-quality grapes and wines.”

The Hunter Valley is a humid area and every season wine growers in the area face the common problem of mildew and fungus. The AMRI list offers 24 chemicals to combat these problems, from azoxystrobin to iprodione, but organic growers such as Mark use what is called a Bordeaux mix, which is a “protective leaf drying spray that has been used way [since] before systemic agrochemicals were developed — just copper and sulphur”.

But even this gentle, old remedy is too much for the biodynamic farmer. Chris Carpenter makes Lark Hill wines using biodynamic techniques. “We use chamomile as a botrytis (fungus) spray because it dries out the spores,” he says, adding that he heard about it from a vegetable farmer. For mildew, instead of the Bordeaux mix, Carpenter uses milk spray. “Copper is far too harsh. It’s highly toxic to micro-organisms (in the soil) and the biodynamic farmer tries to find a way to do away with chemicals.”