The Future of Viticulture In An Age of Environmental Challenges
by Pauline Vicard
The city of Arles in Southern France has everything: it’s picturesque, bucolic and in October features some very sunny days. Once the source of inspiration of Vincent Van Gogh, it is now the home of the World Living Soil Forum, a two-day gathering of global experts, researchers, institutions, trade associations and companies from the food and beverage industry. Co-organised by Moët Hennessy and Change Now, it’s where all facets of soil health, regenerative agriculture and adaptation to climate change are discussed.
I have been involved with the WLSF from the very beginning and was on the board of the 2022 edition. This year, I returned to lead two fascinating conversations and meet with experts from all around the world.
Here are my five takeaways from the forum:
There are three levers of change in viticulture
The goal is simple: being able to continue to produce quality grapes today and tomorrow, and understand how this can be done in the most respectful way for both people and the planet. To achieve this goal, viticulturists are currently working on three issues:
- Gaining a better understanding of how soils work, including its biodiversity and its interaction with minerals
- The selection of vegetal material (the vines themselves and their rootstocks) and its impact on yield, quality and the need to reduce chemical inputs
- The farming practices
Célien Durney is a PhD student in plant biology at the INRAE of Dijon, preparing his doctorate in partnership with Hennessy. He explains why none of these are silver bullets on their own, but need to be part of a systemic approach.
“There are still so many things we don’t understand about soils and their interaction with plants, such as how minerals in the soil are assimilated by plants,” he said. “For us researchers, the aim is therefore to increase the number of analyses in order to understand what is happening on a large scale, but also to understand whether there are differences depending on changes in practices, and to establish the cost-benefit ratio of one practice or another depending on the objectives of an estate or a region.”
There is organic matter, and organic matter
The quantity of organic matter is one of the metrics used to determine the health of a soil: the more organic matter, the better. This is a preoccupation of regulators in Europe, as raising the global levels of organic matter could help with carbon sequestration and be part of the solution to mitigate climate change.
But when it comes to organic matter and quality-focused viticulture, things become complicated.
Thibaut Déplanche is the general manager for Celesta Lab, a laboratory for analysis, study and consultancy in soil biology and recycling of organic products. At the World Living Soil Forum, we discussed his recent learnings, based on thorough soil diagnostics he conducted with Mathilde Boisseau, Wine and Vineyard Director at the Cognac power-house Hennessy, which is supplied by 34,000 hectares of vineyards.
Here is what they learned:
- Of the vineyards they analyzed, the soils had one more percent of organic matter than the national average
- Not only this, but these soils also had twice the microbial biomass than the national average.
- However, despite being richer in microbial life and in total organic matter than other French wine regions, these soils produced, on average, 10 less units of nitrogen and 20% of the plots they studied had a real nitrogen deficit – in a region where the need for yield means nitrogen depletion is particularly important. It’s also a critical consideration, because Hennessy wants to drastically cut its reliance on chemical inputs.
“What we need to understand,” said Déplanche, ”is that nitrogen works very differently than other minerals, such as potassium or magnesium. Nitrogen is unique in the way that it is produced through an annual cycle, by the degradation of organic products.”
He said all the plots where nitrogen was lacking had a deficit in particular organic matter — the young, rather coarse organic matter (50 microns to 2mm) which degrades and regenerates rapidly in the soil. “This transitional organic matter, made of leaves or vine shoots, is highly energetic, and fundamental to our viticulture objectives.”
In other words, it’s not enough to measure organic matter, but to understand which types are most important. This has implications for what type of material is used to build organic matter; the ideal would be locally-produced plant material, such as grape pomace, which would help create a circular economy.
If you want to know what we will be drinking tomorrow, ask a nursery
The topic of vegetal material is truly fascinating for a geek like me. Wineries and estates all around the world might have the same goal — to produce the best possible wine in the most sustainable way — but they face different realities, from financial to environmental pressures.
“The issues we are facing are vast,” said Frederic Gallois, Vineyard and Supply Director for Moët & Chandon and Ruinart. “They are linked to climate change of course, but also to society’s expectations of the way we run our vineyards and our desire to move away from chemicals in order to support the day-to-day work of the vines. And to do that we need several solutions. In all likelihood, there won’t be just one solution for everything, and we’ll have to look for several.”
Nurseries must be creative and support viticulture by proposing an array of options, and in doing so, will influence the wines we will be drinking tomorrow. The wines we will find on the shelves in a decade will probably come from a more diverse pool of genetic material, including vines from conservation and protection programmes.
“In 2019 we realised that we had diversity in our most beautiful plots and that we were losing it,” Gallois went on. “We therefore decided to select the most interesting individuals and to preserve and protect them in the Essentia conservatory, where we have kept 2,000 individuals of the main Champagne grape varieties plus a small collection of Petit Meslier and Arbane.”
According to the IFV (Institut Francais de la Vigne et du Vin), in 2021, there are more than 180 conservatories across the wine-growing regions of France. The National Catalogue lists 136 varieties, for a total of more than 20,000 different individuals conserved throughout the country, offering winegrowers an array of exceptional biodiversity.
But conserving existing varieties might not be enough to answer the growing request from winegrowers and civil society to minimise, if not eliminate, the use of pesticides in viticulture. First authorised in the French national catalogue in 2017, fungal-resistant varieties, or PIWIS, are being developed. Today, there are more than 30 in the National Catalogue, and the interest in them is growing.
“In a year like 2024 with very high mildew pressure, the difference is enormous,” said Gallois. “We’ve gone from 20 treatments on a plot planted with a classic variety to three treatments on a plot planted with a resistant variety.”
Olivier Zekri heads the Novatech Laboratory, the research and development arm of Mercier Nurseries, a global leader in vine plant production. He leads Nathy, their in-house varietal creation programme, which has made the Nathy-Sauvignac resistant variety available.
“There are a lot of development programmes,” said Zekri, “and in the years 2027 to 2035 there will potentially be a huge number of new varieties available to winegrowers. The challenge for tomorrow’s winemakers will be to know how to incorporate them into systems that generate value, for example the appellation systems. How are we going to incorporate them into an AOC specifications? How are they going to sit next to the genetics we are used to? That’s the challenge for the future.”
Rootstock are the missing piece of the puzzle
I have always been very surprised that for an industry that likes talking about its soils so much, we didn’t know very much about rootstocks, and that there is so little research dedicated to such a fundamental part of the plant.
“The vine is like an iceberg,” explained Lilian Bérillon, owner of the eponymous nursery, which specialises in massal selection. “We talk a lot about what we can see, but we don’t talk much about what’s under the water, or in our case, under the ground. A vine’s foundations are its root system. And as long as we don’t invest in rootstocks dedicated research, we’ll have problems with plant decline.”
“The vine is like an iceberg. We talk a lot about what we can see, but we don’t talk much about what’s under the water, or in our case, under the ground. A vine’s foundations are its root system. And as long as we don’t invest in rootstocks dedicated research, we’ll have problems with plant decline.”
Lilian Bérillon
The reason for rootstock development at the beginning of the 20th century was clear: to protect Vitis vinifera against phylloxera. While it saved wine, this simple and unique mandated resulted in the commercialisation of only a handful of varieties, differing mostly in their ability to adapt to calcareous soils. Today there are 17 listed in the catalogue of French nurseries, with 20% of these varieties representing 80% or so of planted vineyards in France.
Almost a century later, this simple mandate is no longer adapted to the needs of quality viticulture.
“In Champagne, almost 85% of vines are planted with 41B,” explained Gallois, adding that while it was certainly the right choice 50 years ago, it is now a limitation, “because it does not cope well with the competition brought about by more sustainable practices, notably cover crops.” He added that they are now testing nine different rootstocks in different situations, “to understand their ability to adapt, and then work with our nurseries to find the ideal selection for each plot.”
You cannot think green if your numbers are red
Finally, this quote from superstar German farmer Benedikt Bösel, founder of Finck Foundation, Gut&Bösel stuck with me: “You cannot think green if your numbers are red,” and it’s easy to understand that it is hard to commit to research, experimentation and transition practices when you are fighting for your livelihood. With the recent terrible vintage that many regions of France experienced and the economic pressure linked to the decrease of consumption, I can only hope that the wine industry will find the energy and the resources to continue to move forward towards more sustainable practices.