10 June 2025
Incorporating a compost extract into the agronomy programme at a Welsh dairy farm has shown that the beneficial impact on soil microbial activity persists.
Sam Carey produces milk from a spring calving herd at Mathafarn, Llanwrin, where he is putting systems in place to create a sustainable and profitable no-input farming business on the former beef and sheep holding.
As part of that ambition and with financial support from the Farming Connect Try Out Fund, Sam has been trialling a new compost extract manufactured by the Soil Ecology Laboratory, a product rich in beneficial bacteria, fungi, protozoa and nematodes.
By supporting soil health and nutrient efficiency he hopes in turn to reduce reliance on synthetic fertilisers.
‘The Goop’ was applied to six fields at varying rates, from a low application of 2 litres/hectare (ha) up to a maximum of 12 litres/ha.
Seven months later, soil analysis showed that the microbial enhancements from the product were still evident.
Goop-treated fields contained more fungi, amoebae and nematodes compared to untreated fields, and these levels had been maintained in that seven-month period from April to November 2024.
The analysis pointed to there being slightly more available nitrogen in the soil where The Goop was applied and little difference in phosphorus levels.
For potassium, the only difference noted was when the product had been applied at a higher rate – soil levels were greater than in the corresponding untreated plot.
Kate Waddams, a researcher at Aberystwyth University who reviewed the results, says it is difficult to put a value on the benefits revealed in the soil analysis without measuring its effect on grass or crop growth but, she added: “If it can replace some nitrogen fertiliser, savings could not only be significant but, with improvements in the soil health, long lasting too.’’
The project also examined how soils responded to the different application rates as the more product used, the greater the cost. Applied at a rate of 4 litres/ha and costed at £4/litre during the study period, it cost £16/ha while at 10 litres/ha the cost was significantly more, at £40/ha.
The results revealed no difference in levels of amoebae and nematodes whether The Goop was applied at a high or low rate.
“This suggests that the lower applications are just as effective as the higher ones,’’ said Kate.
But she added: “When comparing each application of The Goop to its respective control, the higher application rates showed a greater available nutrient value in the soil.’’
For Sam, the results have been sufficiently positive for him to want to continue down the path of improving soil microbiology.
Future options he plans to explore include different application methods, such as inoculating seed at reseeding.
“I am also interested in exploring the soil nutrient levels and their effects on microbiology,’’ he says.
In terms of the Farming Connect trial, he believes the product has its merits, adding: “Application methods have a significant impact on viability of the product which needs further investigation.’’
Sam has long been interested in soil health, participating in an online course run by Dr Elaine Ingham, an internationally recognised authority on soil microbiology.
This course, he says, shone a light on how soil is his farm’s biggest asset and why maintaining its health is so important.
It was a reason why he applied to the Try Out Fund for funding for the on-farm study, to help him better understand how the microbiology in his soils could be enhanced.
The Try Out Fund is a Farming Connect initiative which funds individuals and groups of farmers and growers to experiment with ideas and bring them to life.