If you want to spread mineral fertilisers accurately, the wind should not be too strong. At wind force 3 or higher on the Beaufort scale, spreading mineral fertilisers is not recommended. Spreading fertilisers in high winds can greatly affect the spreading pattern, resulting in spreading paths. The illustration shows the impact of crosswinds on the spreading pattern at wind force 3 on the Beaufort scale. The green line represents CAN. The blue line represents granulated Urea and the red line prilled Urea. It is clear that crosswinds have an adverse impact on the spreading pattern. It is not only wind, but gusts of wind in particular, that have a major impact on the spreading pattern. The influence of wind gusts on the spreading pattern depends on the working width. The wider the working width, the greater the impact of wind gusts.
It is also important to check out the fertiliser to be spread. Some fertilisers are more sensitive to wind gusts than others. When CAN is being spread, the impact of wind gusts is greater than in the case of potash, as potash is more dense and therefore less affected by wind gusts.
When applying liquid fertilisers with water as the transport medium, you are advised not to spray when the wind speed is in excess of 5 m/s. This advice is given to minimise drift.
When nozzles are being used for spraying, the wind has minimal impact.
Various instruments are available for measuring wind force and the strength of wind gusts. These can be measured, for example, with a small wind meter connected to a smartphone.
Bouma, Agrometeorologisch specialist bij Agrometeorologisch Adviesbureau Erno Bouma, 2014.
Prummel & Datema.