How best to respond to costly fertiliser nitrogen


This four-part rapid review aimed to help cereal and oilseed growers respond appropriately to the large increases in prices and potentially restricted availability of manufactured nitrogen fertilisers.

The first three parts were funded by AHDB.

The fourth part was funded by UK Flour Millers (UKFM)

Part one

The first part addressed how to adjust nitrogen rates in response to increases in nitrogen fertiliser prices.

It included an assessment of the impact of these changes on the yield of major arable crops – wheat, barley and oilseed rape.

In addition to the report, the findings were used to develop an online nitrogen fertiliser adjustment calculator for cereals and oilseeds.

Based on the latest AHDB Nutrient management guide (RB209) data, the tool accounts for fertiliser and grain/oilseed prices and calculates the adjustment in the amount of nitrogen (from the typical farm rate) to apply to crops.

Nitrogen fertiliser adjustment calculator for cereals and oilseeds

Part two

Building on part one, this report assessed the impact on other aspects of fertiliser management and includes information on:

  • Which crops, fields and nitrogen splits to prioritise
  • The influence of expected yield
  • Management of organic materials
  • Achieving milling and malting specification
  • The value of precision nitrogen use
  • Calculating the nitrogen price
  • Management of other nutrients
  • Longer-term implications

Part three

Part three examines whether the wheat and barley findings are appropriate for the oats sector and, if not, how oats growers can best respond to the current prices and availability of manufactured fertilisers. Both winter and spring oats crops are considered.

Part four 

Funded by UK Flour Millers (UKFM), the fourth part focuses on the milling wheat market – where the grain protein content affects the price received by farmers. The report builds on earlier parts of the review and explores how to manage late nitrogen application in milling wheat. 


Video: How to identify the optimum nitrogen rate (and when to apply fertiliser) – Pete Berry, ADAS

Cereals & Oilseeds
Project code:
Research Review 97
21 October 2021 - 05 November 2021
Total project value:
Project leader:


RR97 final project report (part one) RR97 final project report (part two) RR97 final project report (part three) Impact of expensive fertiliser – late nitrogen for milling wheat (part four, a UK Flour Millers report)