Terrafarmer has been working with Chris and Bella Mossman at Nant y Bach Farm, near Llangrannog on the West Wales coast, as they continue the move to a lower-input, grass-based dairy system.
For years, Nant y Bach operated as a profitable conventional dairy. But recurring bovine TB breakdowns and persistent livestock health issues prompted Chris to rethink the system from the ground up.
In 2018, he embarked on a regenerative transition with a clear aim: to separate the farm’s profitability from expensive external inputs and to build resilience into the business as a whole. Specific objectives included:
- Reducing reliance on inorganic fertilisers and bought-in feed
- Achieving financial sustainability without recourse to grants or subsidies
- Making the most of the free energy available from sunlight and photosynthesis.
Grassland and soil management
Since 2018, the farm has moved from ryegrass monoculture to multi-species swards across the grazing platform, with diverse mixtures used for all reseeding, for both grazing and silage. The variety of plant types, root structures and depths gives the farm far more flexibility to cope with weather extremes.
Alongside the change in swards, Chris has shifted his approach to soil chemistry and biology, with reduced tillage, a foliar nitrogen programme using a Tow and Fert machine, and limited slurry application via trailing shoe. The most striking change has been on synthetic nitrogen, which has come down from a historical 300kg/ha to 126kg/ha in 2022 and 80kg/ha in 2025, with a target of 50kg/ha.
Biological inputs trial
In 2025, Chris took part in an Innovate UK-funded trial investigating biological inputs, managed by Will Marris at Terrafarmer. The trial was replicated across five farms in Wales, assessing the efficacy of six biological inputs based on soil, leaf tissue and forage analysis. Chris used the data and findings to refine his foliar nitrogen mix and push further towards his 50kg/ha target.
“The project headed by Will Marris from Terrafarmer is precisely what pasture-based farmers need, and needs more of: an independent body trialling different biological products on a significant scale across a number of sites. So much of what exactly happens under the feet of our livestock and their grazing muzzles is as yet unknown. The work Will undertook begins to help pasture-based farming make decisions that unlock the potential of harmonising soil, pasture, livestock and sunlight. The data collected and shared by the trial was impressive.”
Chris Mossman, Nant y Bach Farm
Livestock management
The herd has grown to a stocking rate equivalent of 400 cows, specifically bred for high performance in a grass-based system. An intensive eight-week spring calving block aligns animal demand with the natural grass growth curve, maximising milk solids from grazed forage.
Looking ahead
Despite the lower input levels, the farm aims for a yield of 13 tonnes of dry matter per hectare. Improvements in water infiltration and water-holding capacity have made the soil more resilient to weather extremes, and on-farm emissions have come down.
For Chris, the journey continues. As he puts it: “We need to learn what the farm’s sweet spot is for maximum sustainable output… reducing the need for expensive fossil-derived energy.”
We’ll continue to work with Chris and the team at Nant y Bach as he fine-tunes the system and pushes towards the 50kg/ha target.
We’re here to help
At Terrafarmer, we see consulting as a long-term process and we aim to have an ongoing relationship with all our clients. With many years of practical farming experience and a commitment to sustainable and regenerative farming systems, we’re the right choice. Get in touch for a no-obligation chat on 01347 844132 or send us a message on our Contact Page.
Images courtesy of British Farming Awards
About the author
After studying at Newcastle University, Will worked as an agronomist for six years, delivering regenerative farming advice alongside SFI and soil consultancy. His passion is supporting farmers on their transition to regenerative farming systems, particularly integrating livestock and arable systems to create more robust and resilient businesses.
About the author
After studying at Newcastle University, Will worked as an agronomist for six years, delivering regenerative farming advice alongside SFI and soil consultancy. His passion is supporting farmers on their transition to regenerative farming systems, particularly integrating livestock and arable systems to create more robust and resilient businesses.
