Nitrogen fertilisation in late summer can be extremely beneficial in oilseed rape cultivation under certain conditions. Such a measure is recommended in the following situations:
Cereal crop as previous crop
If oilseed rape is grown after cereals, nitrogen fertilisation may be necessary in late summer. Cereals often leave less available nitrogen in the soil, which can impair the growth of the following oilseed rape. An additional N application helps to compensate for this deficit and secure the nutrient supply.
Tillage without a plough
When tilling without a plough, the nitrogen in the soil can be released more slowly. This can inhibit the development of oilseed rape. Targeted nitrogen fertilisation in late summer can help by providing the necessary amount of nutrients and thus supporting plant growth.
Straw fertilisation
If straw was previously applied to the field as fertiliser, the carbon content increases. This leads to an increased need for nitrogen. The decomposition of straw in the soil consumes nitrogen, which reduces its availability for rapeseed crops. Nitrogen fertilisation in late summer helps to compensate for this loss and promote the growth of oilseed rape.
Late sowing
Oilseed rape sown at a medium or later date may need an additional supply of nitrogen to grow optimally. These plants have less time to take up nutrients from the soil before winter sets in. A late summer fertiliser will provide nitrogen to help them grow strong and healthy into winter.
Visible nitrogen deficiency
If signs of a nitrogen deficiency are visible in the soil or on the plants, an immediate N application in late summer is highly advisable. Visible deficiencies, such as yellowish leaves or weak growth, indicate that the soil does not contain enough nitrogen to meet the requirements of the oilseed rape. Timely fertilisation can remedy this deficiency and ensure plant growth.
