Is there a business case for making large quantities of on farm compost for regenerative farmers?
Compost is a much written about, much debated subject, often talked about in revered terms. And rightfully so. It is the stuff the magic. If done well, composting can turn plant material into a rich soil that is full of nutrients, organic matter and microbial life – medicine for improving soil health.
However, accessing good quality affordable compost was also seen by some regenerative farmers – specifically those managing large hectarage, such as arable farmers, as a major cost barrier to enter regenerative farming. To give an idea of the costs involved – in the Netherlands ‘quality’ compost costs in 2024 was €22 to €23 per m³ (when bought at volume). A farm of around 200ha would need about 1300 tonnes for direct application – a cost of a staggering €40,000 per annum.
So, we thought, could a way around this be to build a business case whereby regenerative farmers could use inputs from their farm, such as mown cover crops and straw, to make their own compost, and create a circular nutrient and carbon cycle on the farm? So, with the support of Patagonia and WWF, we set off upon a journey of discovery, talking to some amazing composting experts across Europe.
And whilst we collected a wealth of information on the trials and tribulations of composting, we very quickly realised that regulatory restrictions, particularly in the Netherlands, but also in many member states throughout Europe, made the production of the amount of solid compost required for a medium size arable farm completely unviable.
The business case idea had to be dropped, but the project was not without significant benefits. We also learnt that the growing of multispecies cover crops (a mainstay in regenerative agriculture), and their composting on field was an important alternative; that regulations would allow for the much smaller production of on farm compost required for compost tea. And that whilst there is no doubt that the application of solid compost across the farm was a major accelerator in regenerating soils, once regenerated, the combination of practices that we apply in regenerative agriculture was sufficient to maintain soil health and organic matter (no till, cover crops, diverse rotations, leaving in roots and crop residues, biodiversity and variety etc.).
Many of your reading this will no doubt be thinking to yourself, livestock. Surely reintegrating livestock back into the arable systems is a failsafe way to recycle organic matter on the farm and improve soil health. And there is well documented proof of this. But livestock restrictions, and cost/risk implications for the farmer to not always allow for this.
We wont be forgetting our on farm composting idea. As society gradually gets behind the necessity of the circular food economy, no doubt regulations will change and adapt. But for now this project has given us a lot to get on with, namely:
- Developing new compost recipes for compost tea and testing their impact on the soil biology
- Looking into methods to increase the surface areas of mown cover crops for more rapid composting on field
- And finding ways to more effectively sow seeds directly through the mown cover crops on the field.
The full report is available HERE