Autumn fertilisation – potassium, magnesium and sulphur are important in autumn, for increasing N-efficiency
Potassium provides a boost for winter
The autumn period is a crucial time for providing winter crops with the potassium they require up until the main growth phase in spring. Oilseed rape will take up up to 100 kg K2O ha-1 in autumn! Winter barley, too, benefits from an autumn application of potassium. During harsh winters, plant and tiller losses can be minimised by ensuring an adequate supply of potassium is available.
Magnesium promotes root growth
Magnesium should not be neglected as it is essential for root growth. Only well-developed root systems assure optimal growth in springtime, providing the best protection against drought stress. The magnesium requirement of oilseed rape in autumn is approximately 20 kg MgO ha-1. The main uptake period for magnesium, however, is in spring, when winter foliage losses need to be replaced.
Sulphur supports efficient N-utilisation
Sulphur is an important component for building proteins and high-quality fatty acids. Only with a sufficient supply of sulphur is efficient N-utilisation possible, assuring optimal development of the crop. Particularly after cooler late summers with above average rainfall plants may suffer from sulphur deficiency in autumn. This may be remedied by fast-acting sulphate sulphur fertilisation, as only the sulphate form is directly taken up by plants.
Korn-Kali provides potassium, magnesium and sulphur
An autumn application of between 300-500 kg Korn-Kali ha-1 is generally applied to oilseed rape, depending on the site, and after the winter will serve as the basis for an optimal start into the new growth period.
Acute S-deficiency? Short-term foliar fertilisation with EPSO-products
In case of acute sulphur deficiency, autumnal foliar fertilisation with 10 kg EPSO Top or EPSO Microtop ha-1 (for barley, use EPSO Combitop) rapidly increases the S supply to the crop and alleviates deficiency.