Sulphur is often seen as the missing link between soils, crops and nutrition, and is often overshadowed by talk about NP and K – but a new study has shown that many soils are deficient on this essential fertiliser.

It plays a central role in the production of amino acids methionine and cysteine – the building blocks of protein in plants – and directly impacts on the nutritional value of human and livestock feeds. Now, soil analysis carried out by Lancrop Laboratories has shown that there is an average sulphur deficiency of 85% across all soils tested.

This suggests that not enough is being used across the UK and or that the recommendations in the fertiliser manual are out of date and need re-evaluating. Sulphur is also a readily leachable element which will need applying each year.

Visually, there is often confusion about the yellowing of crops and which nutrient is deficient – sulphur deficiency showing in younger leaves, while nitrogen deficiency will show up as yellowing in older leaves.

Sulphur plays a key role in allowing nitrogen to be used more efficiently, producing greater yields for the same application of N fertiliser and with the potential to cut rates due to better utilisation. There is also research evidence that shows that its inclusion in a fertiliser programme reduces leaching of nitrates from the soil into water courses.

Fertiliser specialist, Calcifert, had found improvement in yields and quality through trial work across several crops. For instance, trials in oilseed rape with Calcifert Sulphur 200kg, when compared with a control of zero SO3, showed an increase in yield of one-tonne of crop /ha.

Also, trials and farmer testimony had shown increases in both grain and straw yields through the application of Calcifert Sulphur. Further improving grain quality and passing standards for both bread making wheat and malting barleys.

Using it on a trial on a grassland farm in Northern Ireland resulted in an improved profitability of 1.3 ppl which was a result of higher quality forage, higher forage DM yield, and reduced bought-in feed costs. Regular users report increased yields of first cut silage from the early inclusion of sulphur in the fertiliser program.

"Calcifert LS11, our newest product, had the dual effect of liming and providing sulphur, ideal for early spring applications ensuring the soil is in optimum condition. This had shown increases of 10% grass DM yields due to the improved total sulphur application," said a spokesperson.