HOW TO: Increase your forage knowledge

Nutrient management reviewed

The new Nutrient Management Guide (RB209) is the essential reference for anyone planning the use of nutrients and fertilisers in England, Wales and Northern Ireland.

The update is the result of a £98,000 project overseen by the AHDB-led UK Partnership for Crop Nutrient Management and delivered by an ADAS-led consortium of experts from across the UK research community. It was supported by £200,000-worth of in-kind funding by industry.

Farmers, growers, agronomists, breeders, researchers, fertiliser companies and other industry experts were among those consulted on how existing RB209 recommendations could be improved to incorporate the latest scientific advances.

The guide will be published as seven sections including; Principles of nutrient management and fertiliser use, Organic materials, Grass and forage crops, Arable crops, Potatoes, Vegetables and bulbs, Fruit vines and hops.

Key changes for farmers growing grass and forage crops

Nutrient recommendations for grass and forage crops are now presented in Section 3, with the inclusion of guidance on how to use the field assessment method to calculate Soil Nitrogen Supply.

Grassland nitrogen recommendations have been revised to focus on target yield of grass production without linking to particular animal production systems (dairy, beef or sheep), milk yield, stocking rate or concentrate use.

Whole season nitrogen requirements and nitrogen application sequences are provided separately for cutting and grazing situations. The total nitrogen recommendations can be adjusted according to Soil Nitrogen Supply (SNS), Grass Growth Class (GGC) and seasonal rainfall. The recommendations for nitrogen use in autumn grass establishment has been increased.

There have been no changes to phosphate and potash recommendations for grazing, silage or hay systems. Minimum changes have been made to nutrient recommendations for maize and wholecrop silages.

The nutrient recommendations for swedes, turnips, rape and kale have been altered to reflect more grazing in-situ, so fewer nutrients are being removed from the field. The nutrient recommendations for fodder beet have been increased due to higher yields being targeted.

Key changes for farmers using organic materials

Nutrient values for organic materials are presented in Section 2 of the Nutrient Management Guide. Nutrient content figures have been added for goat farmyard manure and farm-sourced and food-based anaerobic digestate. Digested liquid biosolids have been removed.

Nutrient content figures have been updated for horse, cattle, sheep and duck farmyard manure, cattle and pig slurry, biosolids and compost. Nutrient content of poultry manure is presented according to dry matter content.

For farmers and growers producing and using organic materials, the updated figures in the organic materials section will be very useful when calculating their nutrient and financial values. The changes mean that calculations for organic materials are becoming more accurate.

Pick up the AHDB Nutrient Management Guide at Grassland & Muck 2017

The publication is being launched at Grassland & Muck at Stoneleigh on 24 and 25 May. Visitors to the event will be the first to get access to the AHDB Nutrient Management Guide (RB209).

For the latest information on RB209, visit