Bernese Seeland peat upgrades raise yields but face limits

Farmers in the Bernese Seeland farming region are improving sinking peat soils with construction earth, a method that has increased yields but remains controversial, SRF reports.

At a field near Ins, farmer Ueli Kirchhofer is pleased with his potato crop. The plants are green and healthy, and the potatoes are large and unblemished. He attributes the result to recent irrigation from a nearby canal and, above all, to soil improvements carried out several years ago.

Earth from construction spoil depots was mixed with the peat soil, and the entire area was levelled. The resulting soil is loose and crumbly, helping to counter the subsidence of the peat.

Similar work is under way in Gals, where construction machinery is levelling fields to create an even surface. Farmer Matthias Schwab, president of the agricultural association Pro Agricultura, says the work is needed because the peat soils are sinking. During wet weather, more and more lakes form in the fields.

More than 20 hectares near Gals have already been improved, with about 50 hectares still planned. The total cost is around 600,000 Swiss francs. The federal government initially covered about 80 percent of the costs, but the project has operated without subsidies since 2025. The work is now financed through fees for excavated material from construction projects and by landowners.

Critics say the measures are too expensive and labour-intensive and destroy habitats. Biologist Emanuel Egger of Vision 3-Seen-Land 2050, an association of several environmental protection groups, says partially flooded fields provide important habitat for many animals.

The groups are not opposed to soil improvements in principle, Egger says, but they argue that the method does not make sense everywhere and is not a universal solution.

Scientific assessments are still under way, but soil scientist Matthias Stettler already says the improvements are working. He says he did not expect the soils to become so fertile within just a few years.

However, Stettler says a large-scale improvement programme would fail because there is not enough suitable construction material. Millions of cubic metres would be needed to upgrade all the affected land in the Seeland, which he considers unrealistic. Suitable material is becoming harder to find because less construction is taking place on undeveloped land, while some excavated earth is contaminated or otherwise unsuitable.

Stettler says improvements should therefore focus on locations where they make sense. Environmental groups are calling for different forms of agriculture on the affected land, including cattle breeds that can cope with such soils, as well as possible cultivation of rice or reeds for use as building material.

Farmers in the Bernese Seeland believe many more fields need to be improved to maintain the kind of profitable agriculture they know. “We have no interest in producing even less,” Schwab says, warning that this would seriously endanger farming in the region. The existing projects show that the method can work, but the machinery will not be able to operate on every field.