Soils and cropping systems

Conserving soils, building soil fertility and designing systems to produce healthy crops, sufficient yields and quality food are fundamental to ensuring food security and public health. The return of carbon‐rich crop residues to the soil, and the use of green manures and legumes for fertility‐building in crop rotations help to conserve and enhance organic matter levels in soils, soil structure and soil biological activity. Crop rotations and polycultures also help regulate weed, pest and disease incidence, particularly in systems where the use of chemical inputs is restricted.

Our work in this area is focused on the development of productive organic crop ping systems including the use of legumes, cover crops and reduced tillage systems without the use of herbicides. We have demonstrated that complex legume mixtures contribute to fertility building while supporting pollinators, and that reduced tillage can contribute to reduced energy consumption and enhanced soil protection.

Reduced tillage and soils

Ecodyn reduced tillage equipment in trials at Wakelyns
Agroforestry as part of the OSCAR project

Our work on integrating tillage systems and subsidiary crops has shown the challenges and potential of developing these sorts of approaches for, and with, organic farmers. The participatory approach used in TILMAN‐ORG has meant that we have results and experiences from the farmer’s field that can be used immediately by other farmers. In the UK we found that crop establishment was higher in reduced tillage (but unfortunately not yield, which was similar in spring but slightly lower for winter crops). We found weeds to be a challenge but earthworms increased and fuel use was reduced. The key findings across the whole project were that in most cases crop yields under reduced tillage tend to be reduced but not substantially. The use of green manures can mitigate this. However, further work is needed to develop farm‐specific reduced tillage systems through optimised timing of nutrient supply and improved, more adaptable, machinery. Our work in OSCAR (below) is further developed the use of the Eco-dyn tillage system in the UK.An important area of work within this programme is engaging directly with producers. The AHDB Horticulture funded GREAT Soils project is working with both organic and conventional farmers (and their advisors, agronomists etc) to improve their soils. It is being undertaken in a participatory way to ensure that they have the right tools as well as the confidence to ‘read the signs’ from their soils and to take appropriate actions. It is building on our own work in this area (working with a number of collaborators) but also recognises the way in which organic farmers and researchers’ have played an important role in raising the awareness and importance of soil health and fertility for a truly sustainable farming system.

Legumes and cover crops

Given their importance for soil fertility in organic systems, we have continued to work on legumes, cover crops and leys.

Within the OSCAR project we have developed a farmer-friendly, innovative and highly informative information platform – The Cover Crop and Living Mulch Toolbox that includes a communal resource (wiki) for subsidiary crops as well as a decision support tool. OSCAR also looked at the performance of subsidiary crops that are underutilised or new to Europe and the UK, with several new Vicia and Lathyrus species performing particularly well.

In a joint PhD study with Reading University on the biodiversity benefits of legume‐based mixtures (which was initiated as part of the former ORC‐led LegLINK project), Rob Brown found that increased legume species diversity can provides a season‐long forage resource for a wider range of pollinating insects, while also providing a stable environment for earthworm species. However, mowing and grazing management can affect this negatively, with hay production providing the best resource.

Improving productivity

The issue of the productivity of organic crop production remains much debated. In the Defra‐funded Sustainability of organic crop yields and rotations project, we analysed results from several previous studies in the UK to assess whether nutrient supplies were adequate to maintain yields over the rotation. Our modelling found that enough nitrogen is supplied through biological fixation to support typical organic arable yields for at least 3‐4 years following the ley if not lost through leaching, but that imported sources of P (in particular mined rock phosphate) are required to maintain an adequate balance of this nutrient and that large deficits of both P and K can occur in stockless systems.

In 2015 we secured EU H2020 funding for two new projects. The OK‐Net Arable project seeks to address crop productivity and quality issues through an innovative approach to knowledge ex change being pioneered by ORC. This involves facilitating the co‐creation of knowledge by farmers, farm advisers and scientists. We are leading facilitation of knowledge testing with farmer innovation networks in the participating countries for the whole project and will carry out this work in the UK with organic arable farmers.

The DIVERSIFOOD project will build on the progress made in SOLIBAM and other projects to develop sustainable farming systems. It will bring together farmers, scientists, processors, traders and consumers to promote the greater use of diverse plants and produce with a local and cultural identity. This will help to demonstrate how society at large can encourage sustainable agriculture, as well as simultaneously promoting this concept through production and marketing avenues.

The BioGreenhouse project has completed and has produced a wealth of resources on organic protected cropping. The sheep grazing for blackgrass control project will be completed in 2016.

ORC staff involved

Ambrogio CostanzoAnja ViewegerDominic AmosSally WestawayDr Jo Smith, Prof Martin Wolfe

Current projects

Project title (acronym)FunderDescription
Embedding crop diversity and networking for local high quality food systems (DIVERSIFOOD)Horizon 2020DIVERSIFOOD will evaluate and enrich the diversity of cultivated plants within diverse agroecosystems so as to increase the performance and resilience of those systems while simultaneously increasing the range and quality of the produce for consumers.
GREATSoilsAHDB – HorticultureGrowing Resilient Efficient And Thriving Soils
Organic Knowledge Network Arable (OK-Net Arable)Horizon 2020OK-NET Arable aims to improve the exchange of innovative and traditional knowledge among farmers, farm advisers and scientists to increase productivity and quality in organic arable cropping all over Europe, in order to satisfy future market demand.

Completed projects

Project title (acronym)FunderDescription
Winter grazing cereals: The effects on crop-weed competition and grain yieldDFFThis project assesses the question ‘How can the traditional method of grazing winter wheat with sheep optimised to control black-grass populations?’
Towards a sustainable and productive EU organic greenhouse horticulture (BioGreenhouse)COSTTo improve and disseminate knowledge for new and better production strategies, methods and technologies to support sustainable and productive organic greenhouse/protected horticulture in the EU
Optimise Subsidiary Crop Application in Rotations (OSCAR)EU FP7OSCAR studies key factors influencing the success of cover cropping, incl. cultivation methods, machinery and suitable plant genotypes. It develops targeted systems for varied conditions in Europe and assesses them in organic and conventional agriculture.
Strategies for Organic and Low-input Integrated Breeding and Management (SOLIBAM)EU FP7Develop specific and novel breeding approaches integrated with management practices to improve performance, quality, sustainability and stability of crops adapted to organic and low-input systems in Europe and small-scale farms in Africa.
New approaches to weed control in oilseed rapeHGCAThe project tests weed control within the inter-row spacing of oilseed rape using various techniques. This includes positioning systems (e.g. vision-guided) and weed control methods (e.g. chemical and mechanical).
Potato virus Y: epidemiology, control and virus-host interactions (PVY Control)Finnish Ministry of Agriculture and ForestryThe project conducts a monitoring programme for Potato virus Y and its vectors in Northern Finland in order to design viable virus control options for seed potato production.
Using legume-based mixtures to enhance the nitrogen use efficiency and economic viability of cropping systems. (LegLINK)DefraThe three year collaborative project aims to improve soil fertility building in leys by developing targeted species mixtures of green manures, in particular nitrogen-fixing legumes.

See all completed projects here.

Arable bi-cropping for feedSheepdrove Organic Farm and ORCAssessing cereal-pea bi-cropping for home-grown production of feedstuff for monogastrics. 2009.

Completed projects

Project titleFunderDescription
Wheat LINKDEFRA and industry partnersSustainable production of organic wheat. October 2005 – December 2008. Run with Scottish Agricultural College. Additional PDF available.
Blight MOPEUDevelopment of a systems approach for the management of late blight (Phytophthora infestans) in organic potato production. 2001-2004. Additional PDF available.
Non-animal based nutrient sources for organic plant raisingDEFRA2002-2003.
Inter-row hoeingInter-row hoeing and its associated agronomy.
Weeds management in organic systems
Nitrogen expertsDEFRAImproving N use and performance of arable crops on organic arable farms using an expert group approach. 1999-2002.
EcodynORC and Duchy Home FarmAssessing Non-Inversion-Tillage (NIT) with the Eco-dyn in terms of energy use, agronomic and ecological effects in an organic rotation. Start March 2010.

Key publications

Döring T F, Haigh Z, Pearce H, Pearce B, Jones H, Clarke S, Wolfe M. 2009. Variations on varieties: How reliably do wheat varieties perform under different organic farming conditions? Organic Farming 101: 42-43.

S.L. Phillips SL, Shaw MW, Wolfe MS. 2005. The effect of potato variety mixtures on epidemics of late blight in relation to plot size and level of resistance. Annals of Applied Biology 147: 245–252.

Partner organisations

Research partners

Industry partners

  • Abacus Organic Services Ltd.
  • Institute of Organic Training and Advice (IOTA)
  • Organic Farmers & Growers Ltd.
  • Scottish Organic Producers Association (SOPA)
  • Ltd., Soil Association Certification Ltd.
  • The Arable Group (TAG)
  • Organic Seed Producers Ltd.
  • Soil Association Ltd.
  • HGCA Ltd

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