Crop rotation and soil tillage are among key factors impacting cropping system productivity, pest management and soil health. To assess their role in northern cropping systems, we quantified the effects of crop rotation on spring wheat yield in different tillage systems based on a long-term (2005–2017) field experiment in southwestern Finland. In addition, effects of crop rotation on weeds, plant pathogens, and pest insects were assessed. Three types of crop rotation were compared: monoculture (spring wheat), 2-year rotation (spring wheat—turnip rape—spring wheat—barley) and 4-year rotation (spring wheat—turnip rape—barley—pea) under no-tillage and plowing. A diversified crop rotation improved spring wheat yield by up to 30% in no-tillage and by 13% under plowing compared with monoculture. Overall, the yield quantity and quality differences between crop rotations were higher in no-tillage plots than in plowed plots. The occurrence of weed species in spring wheat before herbicide control was highest in the four-year crop rotation and lowest in the wheat monoculture. For plant diseases, wheat leaf blotch disease severity, mainly caused by Pyrenophora tritici-repentis, was lowest in the most diverse crop rotation. On average, wheat leaf blotch disease severity was 20% less when wheat was grown every fourth year compared with wheat monoculture. The effect of crop rotation on stem and root diseases became apparent after 6 years of rotation and the disease index was lowest in the most diverse crop rotation. Neither rotation nor tillage affected the control need of wheat midge (Sitodiplosis mosellana). Based on our results, diverse crop rotations including cereals, oilseed crops, and legumes increase yield and reduce plant disease severity of spring wheat in Finland, with the magnitude being larger in no-tillage systems.

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Cover crops (CCs) have aroused a great deal of interest as a multifunctional measure to improve the sustainability of agriculture. Understanding farmers’ views are important for future farm-scale implementation. A farmer survey was carried out in Finland in 2021 with the aims to gather farmers’ views on agronomic performance of CCs, their environmental impacts and contribution to climate smart agriculture, and understand how farmers’ views on CCs differed depending on farm/farmer characteristics. The farmers’ sample was conventional and organic farms that had selected CCs as a registered measure in 2020. 6493 farmers were invited to answer a questionnaire with 18 statements (a Likert scale, 5 answer choices), and 1130 responded (17.4%). A Cochran–Mantel–Haenszel test was used to measure the strength of the association between ten characteristics of the respondents and 18 statements. Farmers considered CCs to have wide-ranging benefits for soil conditions. Only 21% of farmers agreed that CCs increase the need for nitrogen fertilizer use. 49% of farmers agreed that CCs reduce weed problems. Farmers mostly agreed (ca. 80%) that CCs reduce nutrient leaching and erosion. They were in general more uncertain about CCs’ contribution to climate change mitigation (53% agreed), adaptation (51%), and resilience (58%). In agri-environmental schemes subsidies for use of CCs should aim large-scale implementation with two important target groups: younger farmers (≤50 years) as they were slightly more skeptical than older ones and farmers with less diverse land use as they were more doubtful of benefits provided by CCs.

Cover crops (CCs) may provide many ecosystem services for crop production systems, and interest has increased in the cultivation of CCs among Finnish farmers. Piloting farmers applied for agricultural payments to support the cultivation of CCs (AP-CCs) in 2020. Novel data with a total of 34,515 field parcels with CCs from 5747 farms was used to assess how farmers allocated CCs depending on farm and parcel characteristics. Pioneering farmers often had conventional, large farms with cereal areas exceeding 25%, and expertise with special crop(s). Conventional farmers seemed to allocate CCs to large parcels. The allocation of CCs was not solely dictated by cash crops. Cover crops were planted more frequently in parcels close to waterways. Conventional farmers allocated CCs to parcels with a history of highly monotonous cereal sequencing. Hence, farmers seem to benefit from ecosystem services provided by CCs: increasing spatial diversity, reducing the environmental footprint, and improving soil health. This novel understanding is used to support the implementation of CCs beyond pilot farms and to develop a decision support system for their allocation. The ultimate goal is to support a transition towards more sustainable crop production systems with currently underutilized CCs in high-latitude conditions.

Farmers may promote the cultivation of under-sown cover crops (CCs) in various ways without jeopardizing the yield of a cash crop. With this survey, we aimed to understand how Finnish farmers manage possible challenges with under-sown CCs. A farmer survey was carried out in 2021. We invited 6493 farmers who had selected CCs as a registered measure to answer a questionnaire with 20 statements (a Likert scale), and 1130 responded (17.4%). A Cochran–Mantel–Haenszel test was used to measure the strength of the association between 11 farm/farmer characteristics of the respondents and 20 statements. Responses indicated that farmers often took under-sown CCs into account during the growing season. Sowing was considered an especially critical measure and the CC seeding rate was often assessed with a test run before sowing. Thirty-nine per cent of the respondents had made investments, most often to facilitate sowing. The farmers usually adjusted the fertilizer rate only according to the cash crop. Early harvesting of a cash crop was considered important by 58% of farmers to ensure that the CCs do not hamper the harvest. Farmers harvested cash crops as soon as they matured and were harvestable, though they had mixed views on whether CCs impacted the quality of the cash crop. Subsidized, investing farmers were likely to be oriented towards the benefits from the ecosystem services provided by CCs. Their experiences should be shared among the farming community to support the large-scale implementation of CCs.