Why it pays to make most of February nitrogen window
There is an abundance of grass on most farms this spring due to the mild winter which led to almost a doubling of grass growth rates over the closed period. As a result many may be contemplating skipping an early fertiliser application. But is this wise?
Many farmers regretted having missed the window of settled weather in mid to late January to get some early nitrogen (N) out.
But it now appears that another opportunity has presented itself to get nitrogen out. Does it pay to put out N this time of year?
There have been numerous trials carried out across Ireland over the past 35 years to examine this and they have all come up with a similar conclusion - the best response to early N is achieved by spreading in January.
The next best time is February. This is on the assumption that the grass is going to be eaten by the cow by mid-April, therefore, the longer length of time the N has to work (before the cow eats the plant), the greater the response will be.
For early N to pay for itself, it has to return a yield greater than 5kgs/ha.
The trials which were conducted on numerous sites across the country demonstrated that fertiliser spread in February on average yielded a response of approximately 10kgs of grass dry matter grown for every 1kg of N applied, based on an application rate of 30kgs/ha (24 units/acre). This clearly demonstrates that early N pays for itself. Another interesting point is that statistically, February is a drier month than March, so there should be a reduced risk of N being leached in February than by waiting to spread in March.
Should every farmer across the country put on the fertiliser spreader this week and start spreading?