There was plenty to see at the Drummonds crops open day last Friday (17 June) in Termonfeckin, Co Louth, which had a focus on farm sustainability.

There were plots with mixed varieties to lower disease pressure, fungicide and crop nutrition trials.

One stop on the tour of particular interest to many was on liquid nitrogen, which, in light of the need to cut costs, fertiliser use and greenhouse gas emissions from agriculture, is growing in popularity.

Drummonds has invested in a liquid fertiliser plant and Brian Reilly of Drummonds explained why he sees the product as more accurate than granular fertiliser and more efficient.

Efficiency

He placed efficiency of the product at 65% to 70% and noted that fertiliser rates can be cut by approximately 10% as a result on cereals and grassland.

Brian commented that a winter wheat crop receiving 160 units/acre of nitrogen in granular form would receive 145 units/acre in liquid form.

At the price of fertiliser, you can’t afford to feed the ditches

Part of the reason for this is because Irish tillage farms are made up of small fields with a lot of boundaries. With liquid fertiliser, farmers can stop “feeding the ditches”.

“We find no matter what fertiliser spreader you have, you’re always going to throw so much in the ditch.

“At the price of fertiliser, you can’t afford to feed the ditches,” Brian added.

There was a noticeable level of reduced growth of scutch and brome grasses or cleavers, for example, in the ditches on the farm in Termonfeckin, which has been treated with liquid nitrogen all year.

Soil-applied nitrogen

The fertiliser is soil applied and contains urea and ammonium nitrate. It is also a CCF product, meaning it is all uniform.

Drummonds combines the product with sulphur to improve nitrogen uptake and can also add trace elements to the mix.

Application needs to be with the appropriate nozzles, as Brian noted the nitrogen needs to dribble down into the crop like a hose pipe.

You are targeting the soil, not the leaf, he said. If flat fan nozzles are used or pressure is too high, then there is a risk of scorch to the crop.

The most that is recommended is 1 to 1.5 bars of pressure and windy days should be avoided to ensure the nitrogen is reaching the soil rather than the crop.

He also recommended splitting rates, so if you are applying 100 units, split that application in two and keep the sprayer 700mm above the crop.

Sprayers should be cleaned after use and the driver or guidance system also needs to be accurate, as Brian noted it’s “unforgiving” if this is off, whether that be a missed line or an overlap.