Paddy rice was planted in 13 regions and four cantons north of the Alps in Switzerland in 2023. The average net yield was 3.1 ± 1.5 t/ha. All farmers worked with seedlings, which were planted between mid-May and end of May. The harvest took place in mid-September. The ongoing research compares the years 2022 and 2023 and evaluates the opportunities and limitations of cultivating paddy rice in Switzerland and the promotion of wetland loving biodiversity. The growth of paddy rice plants, different rice varieties, weed control, the influence of soil and on soil are evaluated, the flora and fauna in rice paddies and nearby wetlands and abiotic factors are compared. Farmers surveys on the management practices e.g., about the timing of flooding, transplanting seedlings, harvesting, and the type, amount and frequency of fertilisers are used to compare the differences of the yield between paddies. We found that a high rice yield can be obtained in Switzerland. However, low yields are frequent. Yield success seems to be compromised by years with extreme unfavourable climatic conditions. During favoura-ble years, management plays an important role and especially water table hight and weed management were important drivers for rice yield. Many wetland associated species live and reproduce in paddy rice fields and thus the paddies enrich the Swiss agricultural landscape for species from different groups, among others endangered odonatan and amphibian species as Spotted darters, Natterjack toads, Tree frogs and Yellow bellied toads. The relatively cold autumn in 2023 caused that in some fields most rice inflorescences were not pollinated and had no seeds. The variety experiment from HAFL showed however that there are other more cold adapted varieties that developed seeds successfully. The mesocosm experiment at Agroscope Reckenholz showed that, compared to drained organic soils cov-ered with grassland, paddy rice cultivation reduced the greenhouse gas emissions significantly. The SNF funded project is running until September 2026 and the Master-, PhD- and Postdoc students en-gaged in the project are still collecting field data and analyse the data in order to write peer reviewed arti-cles. We present here a subset of the most important results of the project and will submit the final report with the scientific publications and the implementation in 2026 to all our funding partners.
