The ongoing drought and high temperatures are evident throughout Switzerland this year. Brown meadows, low lake levels, and rapidly melting glaciers dominate the landscape. But what is the situation like in the vineyards of Cave du Rhodan, which have remained green all summer long despite the drought?
Irrigation is crucial
With annual precipitation of about 500 to 600 millimeters, Valais is one of the driest regions in Switzerland. Our vines are accustomed to these conditions. Nevertheless, water is crucial during certain phases.
Young vines, in particular, depend on it. That is why the installation of a drip irrigation system is part of every new planting.
The water reaches the vines directly and hardly evaporates at all. Older vines also benefit from this, especially at the beginning of the growing season. Fortunately, we usually still have meltwater available at that time.
Keep moisture in the soil longer
However, delivering water directly to the vines is only part of the job. Just as important is the question of how long the soil can retain that moisture.
That is why we intentionally plant vegetation in the areas between the rows of vines. In various plots, we sow mixtures of different plant species. In the spring, some of these are rolled. The plant material remains on the ground and forms a natural layer of mulch.
This layer protects the soil from direct sunlight and slows evaporation. Over time, the plant material decomposes and becomes part of the soil again. Especially during long heat waves, every day that moisture remains in the soil longer can make a difference.
However, there is no single solution that works the same way in every plot. Excessive vegetation can actually consume water and nutrients itself. Slope, soil, the age of the vines, and weather all play a role.
Sheep in the vineyard
However, planting vegetation also means more work. Since we don’t use any herbicides at all, the vegetation must be mowed or mulched regularly. This ensures that the vineyards remain well-maintained and can be managed professionally.
On some plots, our Ouessant sheep take care of this work. They keep the vegetation short while also returning natural fertilizer to the soil.
It’s also about the structure of the soil. No machinery drives over the soil and compacts it. A living, loose soil can absorb water and store it for longer. This becomes important as the intervals between rainfall events grow longer.
In a nutshell
Here, we’ll briefly explain a few unique features of Cave du Rhodan.
Why are the vines at Cave du Rhodan still green despite the drought?
Water is applied where the vines need it. Drip irrigation is part of the process for new plantings. At the same time, cover crops and mulch help retain moisture in the soil for longer.
Why is some of the vegetation rolled?
The plant material remains on the ground. It protects the soil from direct sunlight and reduces evaporation. At the same time, organic matter is returned to the soil.
Why does Cave du Rhodan use Ouessant sheep in the vineyard?
The sheep keep the vegetation between the vines trimmed and return natural fertilizer to the soil. In the Divico plot, they also help with pruning.
