Temperature

When spreading granular fertiliser, you generally don’t need to consider temperature, provided the plant is dry. Otherwise, leaf burn may occur. Leaf burn can be prevented by spreading/spraying only when the crop is dry. You can check this by checking at various points in a plot to see if the crop is moist.

In general, you should take the temperature into account when applying liquid fertilisers. It should not be too hot and/or sunny, as this can cause leaf burn.

Liquid fertilisers are better sprayed in the evening when the sun is less bright.

There is less risk of crop damage from spreading/spraying in spring than later in the season. In late summer and autumn, almost no damage occurs as plants are more hardened off by then.

Sources:

AgroWeerAdvies, 2013.

Bouma, Agrometeorological specialist at Agrometeorological Consultancy Erno Bouma, 2014.

(Air) humidity

When applying both granular and liquid fertilisers, it is important that the plant is dry at all times. So wait several hours before spreading after it has rained. Spreading/spraying fertilisers can cause leaf burn. The picture shows leaf burn caused by spraying Urean.

If you spread fertiliser in high humidity or in (light) rain, the fertiliser becomes sticky.

This can cause clod formation, resulting in blockages in the spreader. This can greatly affect the spreading pattern. Make sure the fertiliser spreader is covered with a tarpaulin when humidity is high.

Primed fertilisers in particular are sensitive to humidity during storage and handling. When humidity is high, grains stick together and there is a high risk of clod formation. When applying liquid fertilisers, the crop should be dry.

Sources:

Fertilisation, 2013.

Bouma, Agrometeorological specialist at Agrometeorological Consultancy Erno Bouma, 2014.

PPO

Wind

If you want to spread mineral fertilisers accurately, it is important that the wind is not too strong. At wind force 3 or higher on the Beaufort scale, spreading mineral fertilisers is not recommended. Spreading fertiliser in high winds can strongly influence the spreading pattern, resulting in spreading lanes The illustration shows the influence of crosswinds on the spreading pattern for a wind force 3, according to the Beaufort scale. The green line represents KAS. The green line represents Urea granulated and the red line Urea prilled. It can be seen that crosswinds have a negative impact on the spreading pattern. Not only the wind, but wind gusts in particular have a great influence on the spreading pattern. The influence of wind gusts on the spreading pattern depends on the working width. The larger the working width, the more important the influence of wind gusts is. It is also important to consider the fertiliser to be spread. Some fertilisers are more sensitive to wind gusts than others. When spreading KAS, the impact of wind gusts is greater than for potash. This is because potash has a higher density and is thus less affected by wind gusts.
When applying liquid fertilisers with water as the transport medium, the advice is not to spray when the wind speed exceeds 5 m/s. This is advised to minimise drift.
When spraying with nozzles, the influence of wind is small.
There are various measuring instruments to measure wind force and strength of wind gusts. These can be measured, for example, with a small wind meter on a smartphone.

Sources:
Bouma, Agrometeorologisch specialist bij Agrometeorologisch Adviesbureau Erno Bouma, 2014.
(KAVB, 2007.
LTO Noord
Prummel & Datema.

Slopes

Spreading on slopes greatly affects the spreading pattern. This is caused, among other things, by the spreader hanging at an angle.

The following points of attention are important when spreading on slopes:

• When spreading a field with slopes, do not choose a large working width. Do not spread too wide in steep slopes.
• When edge spreading, it is often the case that if you spread at an angle against the hill, you will spread further downhill than uphill. You can respond to this by adjusting the disc rotation speed with a hydraulic spreader;
• With some spreaders, spreading on hills has a negative impact on the spreading pattern. This is caused by the fertiliser ending up in a different place on the spreader disc;
• If you use a weighing spreader on slopes, the weighing system may no longer work accurately. This is because when spreading at an angle in the hill, the weighing cells of the spreader are affected. This is because the distribution of fertiliser in the tub is uneven. This can be solved by a built-in inclination sensor. This sensor then provides a correction;
• When spreading hills, it is advantageous to use a speed-dependent metering system, as this allows slip to be detected when driving uphill.

More security. Fewer losses.

A modern farmer wants to work smartly and efficiently. In doing so, he needs information to determine the best time to spray, spread, mow or optimise animal welfare.

This is possible with the updated and expanded ‘Agro Weather App’ developed by OCI especially for farmers. Depending on the planned agro-activity, this app indicates the optimal moment to get going.

The ideal moment is displayed in a detailed overview. Per activity and per three hours. The data can be retrieved by GPS location. Finally, it is possible to plan carefully several days ahead.

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