Pre-empting the forthcoming ban (due to take effect on 1 January 2021), Marc Desom (Desom Estate and Cellars in Remich) has not used a drop of glyphosate in his vineyards for the past four years. However, in his view, not even this step strikes at the heart of the matter. What really interests him is to plan and work towards ensuring that the connection between soil and plant is as naturally balanced as possible.
Luxembourg was the first country in the European Union to strictly prohibit the use of glyphosate. On 1 January 2021, the molecule that proved a boon first to Monsanto and then Bayer will be banned in the Grand Duchy. Showing foresight, many winemakers have pre-empted this political decision. Many have completely changed the way they cultivate their vines and terroir. One such winemaker is Marc Desom, the young head of Desom Estate and Cellars in Remich.
He explains the concepts he has introduced in all his parcels as he makes his way through a recently planted parcel of Pinot Gris in the Goldberg terroir near Stadtbredimus. Here, the vines are scarcely four years old and clusters of grapes are already forming. Wild flowers flourish between the rows: “I have sown specially composed seed mixes,” says Marc Desom. “Flowering plants attract insects encouraging biodiversity and leguminous plants fix nitrogen from the atmosphere to their roots enriching the rather poor local soil without adding any synthetic fertilisers.”
His vision of cultivating vines therefore involves allowing nature to flourish without any artificial input, rather than chemically adjusting indicators to ensure a good harvest. In this context, “abandoning glyphosate is merely part of a much bigger picture” – a genuine mission that instils his work with much deeper meaning. “You have to plan and adapt – it’s much more interesting to work in this way.”
Where soils need to be reconstructed, creating the right balance between the vines and their terroir requires planning, care and hard work.
Indeed, these tasks differ from parcel to parcel, and specific concepts are applied to each of them. Here in Goldberg, the land was consolidated several years ago. “Earthmoving machines were used, leading to a loss of humus,” he points out. “Organic matter must therefore be created to nourish the vines.” Before sowing the seed mixes, Marc Desom therefore applied some woodchip mulch. Once the plants sown among the rows stop flowering, he will roller over them to break the stems and thus lay them flat against the soil. “I plan to leave it without removing anything – it will turn into humus, retain moisture during warm spells in summer, and this plant cover will also limit erosion in periods of heavy rainfall.”
However, although wild flowers are welcome between the rows, they are barred from the area beneath the vine stocks where they would compete directly with the vines. Not only would they limit the nutrition available to the vines, but the moisture they contain could also create breeding grounds for fungal diseases (mildew, oidium, etc.). To ensure good vineyard health, it is therefore necessary to till the soil beneath the grapes to prevent weeds from growing. This must be done in a specific way using various types of equipment, each of which has a dedicated purpose.
“If the soil is very compact, it is a good idea to use a rotary star tiller as this breaks the earth into clods,” says Marc Desom. This machine attached to the back of a tractor breaks up the earth around the vine stocks. “It’s useful in recently planted vineyards like this one as it slices horizontal roots and forces the vines to develop vertical roots.” The more deeply rooted the vine stocks are, the easier it is for the plants to access water during dry spells. They are also better equipped to immerse themselves in mineral elements that instil the wine with the specific characteristics of the area in which it is produced.
If the soil is looser, for instance if a rotary star tiller has already been used, it may be sufficient to attach a griffe (a pronged tool) to the rear of a tractor. This turns over the top layer of soil and clears weeds from the surface. Finally, it is also possible to mow weeds using a third, very recently designed device. This is a kind of strimmer that mows the plant cover without touching the soil, thus achieving similar results to a roller.
Abandoning glyphosate is merely part of a much bigger picture.
It is therefore absolutely possible to do without glyphosate or any other systemic weedkiller (i.e. agents that rely on penetrating the interior of plants) including in Luxembourg where winemakers are proving this point on a daily basis. However, such steps require considerable investment as the machinery is expensive. Each item costs between €8,000 and €12,000 depending on the model. A powerful tractor is required to pull equipment due to the high level of resistance experienced when using a rotary star tiller or griffes.
In addition to the financial outlay, the whole process takes time, particularly in young parcels planted on consolidated land. “Where soils need to be reconstructed, creating the right balance between the vines and their terroir requires planning, care and hard work. It takes 7 to 10 years to achieve a good outcome,” assures Marc Desom. “However, once this harmony is achieved, it will continue to give good results and not require as much work.”
At that point, the vines are old enough to feed themselves. This is when they truly begin to flourish. Patience and commitment are therefore two cardinal virtues when it comes to producing good wine.