Integrated cropping system at Balruddery Farm, Scotland

Balruddery Farm is a 178-hectare arable farm situated 67–163 metres above sea level in a temperate Atlantic maritime environment, with average annual rainfall of 800 mm and a mean annual potential water deficit of 50–75 mm. Soils are imperfectly draining Balrownie Series with an average pH of 5.7, topsoil depths of 25–40 cm, textures ranging from sandy loam to sandy silt loam, and stone contents of 10–20% by volume. The climate has moderate exposure and moderate winters with 50–110 day degrees Celsius of accumulated frost, representing typical conditions for arable cropping in north-east Scotland.

To test, at a commercially realistic scale, whether an integrated arable cropping system can deliver improved environmental outcomes and higher levels of public goods compared with conventional practice, and to quantify the on-farm economic trade-offs during the transition from intensive to low-input management, informing the design of financial incentives for regenerative farming.

Challenges addressed

The system mainly addresses environmental management, in particular biodiversity loss and soil health on arable land. It also addresses socio-economic challenges by seeking an economically efficient path to more sustainable farming.

Costs of NbS

The study follows a 22 ha integrated cropping system at Balruddery Farm near Dundee during the first six years of transition from intensive farming. The rotation covers beans, potatoes, oilseed rape, barley and wheat. Variable costs for fertiliser, pesticides and fuel average about EUR 930 per ha per year (2023 prices); labour and machinery costs were left out as they did not differ between systems.

The integrated system delivers better environmental outcomes than conventional farming, supporting farmland biodiversity. Straw is chopped and returned to the field rather than sold, helping to maintain soil organic matter. Crop sales over the full rotation bring in about EUR 2,390 per ha per year, leaving a gross margin of about EUR 1,700 per ha per year (2023 prices). That is around EUR 600 per ha less than under conventional farming, because the environmental public goods the system provides have no market price for the farmer.

Benefit–cost ratio

The integrated system reaches a BCR of 3.05, so crop revenues comfortably cover input costs, but this is below the 4.66 of the conventional system during the transition. Payments for the environmental benefits the system provides are therefore likely to be needed for farmers to switch.

Establishment of a split-field experimental design comparing conventional and integrated management across six fields over a six-year rotation. Integrated measures included conservation (non-inversion) tillage, tied-ridging in potatoes, compost amendment before sowing, straw chopping and incorporation, cover crops before potatoes and beans, mineral fertiliser rates based on soil nitrogen supply, clover co-cropping, blight forecasting, threshold-based pesticide applications with dose reductions, mineral biofortification, targeted weed control promoting diverse weed flora, and wildflower margins. Yield, input and economic data were collected annually and analysed using median commodity prices from 2011–2016 to avoid incorporating price fluctuations.

Michaela Roberts, The James Hutton Institute, michaela.roberts@hutton.ac.uk

Study overview

The Centre for Sustainable Cropping (CSC) at Balruddery Farm, near Dundee in north-east Scotland, is a long-term experimental platform established by the James Hutton Institute in 2009 to test whether arable farming can deliver improved environmental outcomes while maintaining commercial yields. It is, to the authors' knowledge, the only UK platform of its kind operating at a commercially realistic scale.

The platform uses a split-field design across a 42-hectare block of six arable fields, comparing two cropping systems side by side over a six-year rotation of potatoes, winter wheat, winter barley, winter oilseed rape, spring fava beans and spring barley. The conventional system follows standard commercial practice for the region, while the integrated system combines best-practice measures targeting soil health (conservation tillage, compost amendments, cover crops, straw incorporation), crop nutrition (legume undersowing for biological nitrogen fixation), crop protection (disease forecasting, threshold-based applications, bio-fortification) and biodiversity (wildflower margins, targeted weed control, integrated pest management). Previous work at the site demonstrated improvements in soil properties, broadleaved weed diversity and overall environmental sustainability.

Researchers used the first full six-year rotation of data to carry out a cost-benefit analysis comparing the two systems, considering fertiliser, pesticide and fuel costs alongside crop output. The analysis revealed that environmental gains from agroecological farming are largely public goods, such as biodiversity and soil maintenance, that have no direct market value. This evidence on the private costs of providing public goods informs the design of financial incentives to encourage uptake of regenerative farming practices.