Paying attention to soil health has the potential to produce disease-resistant vines which in turn produce grapes that ripen with minimal need of fungicides and herbicides. Healthy soil also makes vines more resilient to climate change, whether by locking in water to combat drought, or by absorbing water when faced with floods. Not only that, it has the potential to lock in carbon from the atmosphere, making vineyards an asset in the battle to reduce greenhouse gas emissions. Launched in March this year, a new global organisation, The Regenerative Viticulture Foundation, has brought together producers, academics and journalists to share knowledge and understanding of this approach to viticulture, believing that regenerative should become the new conventional.
So what is regenerative viticulture?
First of all, there’s nothing new about it. It's simply a very traditional, pre-chemical-fertiliser approach to agriculture, reinvented for today’s challenges. On a two-day introduction to the subject, hosted by Justin Howard-Sneyd MW and Dr Nathan Einbinder at Dartington Hall in Devon, we learnt that regenerative agriculture should be viewed as a toolkit rather than a prescriptive set of rules. The specific farming requirements of a vineyard owner in England will be significantly different from those of a grower in California but both can adopt regenerative practices that will work with what they have to improve soil health and biodiversity with the outcome of healthy, more resilient disease-resistant vines.
Definitions vary but essentially, regenerative viticulture involves a mindset shift to focus on ‘healthy, living soil, contributing to biodiversity restoration and climate mitigation’ (Giller et al., 2021). This goes beyond sustainability to create actual net-positive benefits both locally and further afield. While a number of the methods employed are reminiscent of biodynamic viticulture without the air of mysticism, proponents are clear that those farming at all levels – conventional, sustainable, organic or biodynamic can make changes that will improve their soil health, positively impact on their vines and at the same time, lock up carbon in their soil.
Regenerative vs organic viticulture
What is it that makes regenerative viticulture a better option for some than organic farming? Also present at Dartington Hall were two producers of English wine. Both were keen to bring regenerative practices to their vineyards but currently farm conventionally (so use herbicides and fungicides where necessary) although one was trialling plots of organically farmed grapes. It was interesting to hear first-hand how, in many situations, organic farming and official certification are not only incredibly difficult to achieve but can actually be damaging to the soil.
For example, the controlled use of copper-based sprays to combat downy mildew, a common fungal disease in humid climates that, left untreated, can wipe out entire vintages, is a permitted organic treatment. Despite tight controls on annual usage levels, copper can accumulate in the soil, significantly reducing biodiversity which, in turn, leads to reduced vine growth. What’s more, because many organic treatments are less effective than conventional alternatives, tractors often have to make more passes through the vineyard to respray. That can lead to compacted soils, poor water infiltration and a reduction in micro-fauna and other organisms necessary for soil health and nitrogen production.
Increasing sustainability for organic producers might therefore involve an increased focus on soil welfare, taking samples and recording details of flora and fauna across the vineyard. Soil disturbance would be minimised, while specific crops, chosen with the soil requirements in mind, would provide year-round vegetative cover. The long taproots of radish plants, for example, help break up compacted soils while legumes usefully fix nitrogen. Such methods lead naturally to stronger, healthier vines, with less need for spraying.
Carbon sequestration
The idea that carbon sequestration – small increases in soil organic carbon (SOC) across large areas of agricultural land can significantly reduce atmospheric carbon dioxide – presents an exciting opportunity. Even conventionally farmed vineyards will already be capturing carbon, and though some farming practices can reduce SOC levels, one that seems to make a positive difference is a move to ‘no-till’ cultivation.
Tilling is a popular method of weed control with those who have a continuing concern with the safety of herbicides like glyphosate – but it disturbs the soil, releasing carbon into the atmosphere again. No-till usually involves using cover crops, as described above. These can be mown and allowed to mulch into the soil or be grazed by sheep or cattle, though animals also have a taste for grapes and vine leaves and there are limits to the time of year when they can be employed! Manure is also an important contributor to soil health with some studies showing that animal integration delivers the highest mean soil carbon sequestration rate.
So does it lead to better wine?
‘Better’ is subjective, but there does seem to be some evidence that regenerative viticulture can produce wines more expressive of their terroir. Certainly, many excellent wines are produced regeneratively, including those of Tablas Creek, Eyrie, Domaine Gauby, Cullen, Reyneke and – launched with an impressive manifesto and much fanfare in 2021 – Saint-Emilion star, Cheval Blanc. The exact link is tricky to pin down, however. Jason Lett of Eyrie Vineyards, Oregon, suggests that the more diverse mix of plants above ground leads in turn to a diverse mix of soil micro-organisms underground which integrate with the vines. He believes these interactions contribute to character and flavour differences between his single-vineyard wines.
Others have made the link between terroir and soil health with Lazcano et al (2020) noting a link exists but also identifying a need for more research to improve understanding. Here, the toolkit approach to regenerative viticulture can be challenging as there are many different strategies and options that must be considered both in isolation and in combination with others.
Regenerative viticulture as a movement is still in its infancy and more research is needed to identify exactly which tools in the toolbox contribute the most to the quality of wine, soil health and carbon sequestration. As an inclusive movement that places emphasis on the flexibility and freedom to apply the methods that work for you, there is currently limited demand for certification among practitioners. Tablas Creek became the first certified Regenerative Organic vineyard in 2020 and at the time of writing is one of only four worldwide. Without an agreed standard, however, it can be difficult to separate meaningful activity from a good story.
The exciting possibilities in this area mean we shall be following the scientific research with interest given our focus on biodiversity and the potential to help us achieve our 2040 carbon targets. We also hope to bring you updates from Wine Society producers present at the Dartington workshop who are moving towards a more regenerative approach – so you can taste for yourselves the impact of these practices on the wine in your glass.
How can I find out more?
The Regenerative Viticulture Foundation website – regenerativeviticulture.org contains links to a number of podcasts, video clips and academic resources.
The film Kiss the Ground (available on Netflix at the time of writing), possibly a bit ‘Hollywood’ for some, is nonetheless an engaging introduction to the subject of regenerative agriculture.
Wine writer Jamie Goode’s new book, Regenerative Viticulture is an accessible but science-based introduction to the subject.
