Tailoring Nitrogen applications – Farmers Guardian

Optimum application rates for winter cereals are typically 50kg/ha lower as a result of the current high nitrogen prices Tim Kerr, Hutchinsons crop nutrition manager told the Hutchinsons Healthy Soils Open Day in Runcorn, Cheshire.

The agronomy company’s assessments of nitrogen responses in 2022 winter wheat crops found that the first 150kg/ha of nitrogen applied gave a yield response of 5.5 tonnes per hectare, Mr Kerr explained.

“But after this it tails off rapidly and the next 100kg/ha of nitrogen gives just 1t/ha of yield.”

With nitrogen use efficiency for the industry currently averaging around 60-65 per cent, improvements of 10-15 per cent could make a real difference in the ability to reduce nitrogen requirements, Mr Kerr explained.

“Start by testing what is in the soil starting with a standard N-min test. Test grain for N content and then you can multiply your yield by grain content to work out your nitrogen offtake and get a benchmark NUE.”

Small tweaks such as calibrating spreaders and tray testing will all add up, he said.

“Foliar N is good but you need foliage to apply it – once crop is established and base N has been applied, you can use foliar. This bypasses the soil and goes straight to the leaf.

“There is a risk of scorch but there are products aimed at providing slow release safe nitrogen which can be tank mixed very easily, so it’s safe to the crop and provides nitrogen over a number of weeks and it has greater efficiency than going through the soil. Foliar N can also help to overcome some of the issues associated with dry soils and nitrogen uptake we saw this spring.

“We have seen 40kg/ha might be dropped off recommendations and be replaced with foliar N very effectively, so you don’t lose your yield potential.”