Nitrogen-fixing bacteria could help arable farmers slash costs

Arable farmers could slash fertiliser costs, boost yields, and protect the environment following the launch of a new nitrogen-fixing bacteria mix.

Developed by Jim Brown at Soil Systems, Enfixa is a combination of nitrogen-fixing and nutrient-solubilising bacteria, which fix atmospheric nitrogen and turn it into a usable source for the crop. It can be used in either organic or conventional systems.

Mr Brown, who developed and uses Enfixa on his 600-acre farm near Newbury, Berkshire, says arable trials have shown producers using Enfixa can halve their nitrogen applications without sacrificing yield. “And when applied with half-rates of applied nitrogen, we have boosted yields by up to 17% in oat crops on our farm,” he adds.

The bacteria, which are supplied in a liquid suspension, can be applied to arable crops or grassland using a normal sprayer, ideally with a sugar source like molasses. “Spring applications are best, but Enfixa could be used as a top dressing in autumn if the soil is still warm,” says Mr Brown.

Retailing at £80 a litre and applied at a minimum of 250ml/ha, ideally split into two applications, it compares very favourably against ammonium nitrate or urea fertiliser costs of around £75/ha for autumn crops, or £150/ha for spring crops.


As well as fixing valuable nitrogen from the air and making it available to the plant, Enfixa bacteria also assimilate and store spare nitrogen in the root zone, says Mike Harrington, independent agronomist at Edaphos. “When nitrogen fertiliser is applied there is more available than the plant can immediately use. This spare nitrogen can easily end up leaching into the groundwater, but with the use of Enfixa it is captured and then gradually released, providing a steady supply to the crop without unhealthy growth flushes.”

Enfixa also releases phosphate and trace nutrients from unavailable stock in the soil and promotes better uptake in the plant, with treated crops showing 60% higher tissue levels of nitrogen, as well as higher levels of phosphate, potash, and trace nutrients.

However, the nitrogen content of Enfix is negligible, meaning its use is unrestricted in organic systems and Nitrate Vulnerable Zones, says Mr Harrington. “It can therefore help producers to maintain or boost yields, while complying with NVZ regulations and protecting the environment.”