Fertiliser spreader calibration has become a hot topic in recent months as many farmers have experienced issues with spreading protected urea on their ground.
These spreading difficulties have mainly been coming from protected urea with sulphur (S), the likes of 38:0:0 + S has proven to be a difficult spread with striping occurring on many farms as a result.
Striping occurs when the product is not spread evenly across the field or when the product breaks apart before it reaches the whole distance it is intended to spread to.
However, grass growth was certainly back from recent years in 2024 with wet conditions experienced in early spring, followed by cold, dry weather in the summer months which left it difficult for grass to take off.
However, before farmers blame the poor weather for poor response from protected urea or the difficulty in spreading the product, they should fully service the fertiliser spinner and make sure all discs and vanes are in good condition and calibrate the spreader accordingly from fertiliser to fertiliser.
Fertiliser calibration
It has to be understood that proper calibration not only maximises the benefits of fertilisation, but also minimises the risks of over- or under-application, which can lead to yield losses, environmental pollution, and increased production costs.
Often, farmers assume a fertiliser spreader is in good condition but it is not uncommon for spreading veins to be worn which greatly affects the spreading distribution.
As vanes wear out over time, this will result in uneven spreading, resulting in areas of over- or under-fertilisation and by simply replacing worn vanes promptly, farmers can maintain consistent application rates and optimise fertiliser efficiency.
The basics also apply, as regular maintenance is crucial, including cleaning, lubrication, and inspection of components, to ensure proper functionality.
It can also be useful to give the spreader a quick rinse after every use as fertiliser sitting on steel often leads to rusting and damage.
One crucial thing to remeber is that different fertiliser types have different particle sizes and densities, leading to variations in spreading behaviour.
This means that adjustments to spreader settings are needed to maintain an accurate spread width and flow rate, and achieve uniform coverage across the field.
At this time of the year, farmers are more than likely getting out one fertiliser as nitrogen (N) application in the early spring is advised.
However, when farmers are swapping between compounds and straight urea or calcium ammonium nitrate (CAN), spreading calibration will have to be changed as well.
Failure to adjust spreader settings to suit the product can result in uneven distribution and sub-optimal fertiliser utilisation.
Headland control is another feature on a spreader that farmers can utilise as it allows operators to adjust the spread pattern when spreading at the field’s edges, preventing excess application in headland areas.
By using this, farmers will not waste valuable fertiliser and will not overlap, therefore leading to more efficient spreading and little wastage of valuable product.
With rules, regulations and limits becoming more stringent on fertiliser spreading dates, quantities and product type, it is crucial for farmers to have their fertiliser spread efficiently and effectively by having vanes, speed and calibration right before spreading.
All fertiliser spreaders come with a manual on what the machine should be calibrated to and at what speed fertiliser should be spread for different rates and fertiliser types, but often these books are not used.
Likewise, there is usually an app that can be downloaded for your certain make of fertiliser spreader, where speed and calibration can be calculated by adding in the type of fertiliser and what rate you want to spread at.
To be effective with your fertiliser this spring is to avail of these books and apps and to service your machine before spreading.
