Climate change threatening Riesling wine

Martin Schömann proudly shows the mix of wild plants growing alongside his vines on the steep slopes of the German wine region of Moselle. Riesling vineyards stretch as far as the eye can see.

"Despite being a wine monoculture, we foster biodiversity in the soil," Schömann told DW. "Plants aren't the enemy, they're our friends."

Read more: Why biodiversity loss hurts humans as much as climate change

Schömann was the first grower in Central Moselle to turn from conventional to organic wine. Wild strawberries, mullein and lemon balm now share the earth, water and nutrients with the vines on his six hectares (15 acres) of land.

 A glance across the sweeping landscape is all it takes to see that Schömann's approach is the exception. His land is surrounded by grey soils that appear devoid of life except row upon row of grapevines.

Once the vines sprout their first spring shoots, most winemakers spray them with synthetic pesticides to kill unwanted plants, pests and diseases.

Read more: Over 40 percent of insect species face extinction: study

The spraying season has come to Moselle early this year, and experts say climate change is to blame — not just for the vines budding prematurely, but also for the new threats they face. 

Higher temperatures actually help grapes grow, and even make them sweeter. But they give fungal diseases a boost too, Eric Lentes, head of the viticulture department of DLR Mosel, a public body that advises winemakers, explains.

Read more: Germany's farmers feel the heat of climate change

On top of this, pests from southern Europe are moving north. Winemakers in the Moselle have no choice then: They must protect their vines, even if that means using more pesticides.

One step forward, one step back

Organic labelling is prized in Germany, yet more than 90% of the country's farms still use synthetic chemical pesticides, with the average farm consuming around 9 kilos (20 pounds) of plant protection products each year, according to figures from the German Environment Agency (UBA).

Lentes told DW there's been a trend of reducing pesticides use through better understanding of fungal diseases and the development of alternative ways to protect grapevines. Growing specific combinations of plants between vines, for example, can help absorb excess water and reduce the fungal growth.

But he says that "due to climate change, the progress we've achieved has been eaten up."

Indeed, pesticides sales in Germany have risen slightly since 2010. A survey from 2015 shows that new pests and fungal diseases are partly to blame for this increase, along with other factors such as the ban of some highly effective pesticides.

Read more: Glyphosate: EU agency must release censored study, court says

To spray or not to spray

Lentes believes Riesling wine as we know it can't survive without pesticides. And although the public debate over agricultural chemicals often divides farmers into good guys and bad, he says things "aren't so black and white."

Read more: Insect protection law mooted by German minister

Organic farmers do in fact use pesticides, such as copper. Although a naturally occurring element, copper is toxic to microorganisms in the soil.

Unlike synthetic chemicals that seep into plants to make them resilient to attack, organic pesticides stay on the surface of the vine. That means they don't get into the grape, and in turn into the wine and our bodies. But it does mean they are easily washed away in a shower of rain, meaning farmers have to keep applying them, over and over again. 

Read more: Smoky wine: A taste of climate change

Conventional farmers, meanwhile, are quietly turning to more sustainable practices that don't earn them the organic label. For example, some winemakers only spray pesticides directly under the vine so other plants can grow around them and make for a more diverse ecosystem. 

Yet making the leap from greener farming to fully organic is something most farmers aren't ready for. 

The high cost of green farming

Organic agriculture demands more investment and is less profitable, at least for now.

The wild grasses Schömann allows to grow in vineyards compete with his vines and reduce their productivity. "We have to think of it as if an additional person sits at your table and you have to share the food," he says. 

That makes wine more expensive, and consumers still aren't ready to pay. The German public talks up its love of organic products, but sales figures reflect a different reality, says Lentes. "When it comes to the wallet, the truth speaks."

Although organic wine is catching on all over the world, it is still a niche that makes less than 4% of global market share, according to wine consultancy IWSR. 

Refusing to pay more for our groceries means the price is passed on elsewhere, says Karl Bär, agriculture and trade adviser at the Munich Environmental Institute.

"We're paying a high price by a loss of biodiversity, by increasing climate change, but also in question of health," he told DW, speaking from Brussels, where he's pushing for a more sustainable agricultural system.

Bär believes an organic future for Europe is perfectly possible, but farmers and consumers will have to get used to changing products and prices. And laws will have to change, too. 

Bär argues that the European Union should put an end date on the production and import of non-organic agricultural products. 

In the meantime, Schömann is trying to talk other winemakers into making the switch to organic.

"I've already convinced two in neighboring villages," he says. "We have to take the risk."