The recommendations in this section are using the RoI fertiliser classification system and are based on Teagasc research.

Due to slight differences between the RoI and NI classification systems, these recommendations are only a guide for Northern Ireland farmers. They can be converted between the RoI and NI classification systems using this Conversion Table

With the introduction of the Nitrates Directive in recent years, the way in which farmers can spread nutrients such as Nitrogen and Phosphorus has dramatically changed. The quantity of Nitrogen and Phosphorus that is legally allowed to be spread by a farmer is now mathematically deduced using a number of steps. It is important to get advice from your local Teagasc advisor or consultant when drawing up Nitrogen and Phosphorus requirements and allowances for the year.

Before choosing your fertiliser products please consult your local advisor to ensure that you do not exceed the limits for your farm as determined by the nitrates directive (SI no 610) of 2010.