Sep 27, 2013
Autumn application serves as a basis for high yields next year
Autumn application of appropriate fertilisers positively influences yields in the spring season. The early nutrient supply serves as a foundation for high yields and excellent crop quality. Autumn application of potassium and magnesium is the best way of providing nutrients during the early stages of plant development. In the case of rape, this helps plants to develop a deep and extensively branched root system, as well as strong root necks. Autumn application also initiates side and main shoot growth.
International trial results document this effect. Based on the results of a field trial conducted in Wieszczyczyn in Poland the chart clearly illustrates the importance of autumn fertilisation for yield and quality of winter rape. In comparison to the unfertilised control field, the yield of the field fertilised with Korn-Kali® in in the autumn was increased by 40 %. The combination with a spring application of ESTA® Kieserit seems to be especially beneficial, as this meets the high magnesium demand during the growth phase.
Use autumn application to raise winter hardiness now
Another important reason for autumn fertilisation is increased winter hardiness. In recent years, long hard winters and sudden frost periods have resulted in considerable crop losses. Sudden and severe cold spells, extremely low temperatures and alternate freezing and thawing create stress to plants, and may lead to significant winterkill damage. Potassium and magnesium increase winter hardiness, thereby creating optimum protection against the three most threatening effects of winter: intracellular ice formation, winter desiccation and heaving.
Intracellular freezing kills plants by rupturing cells. The only way to protect plants is to provide potassium and sugar for storing in cells. Both substances will lower the freezing point of the cellular fluid, acting as antifreeze agents. A sufficient supply of potassium to cells is therefore necessary before winter really sets in. Once the plant has weathered the cold, its potassium content will ensure optimal development and will raise the plant’s tolerance against drought stress.
High content of potassium secures yields
Test results from Trüstedt in Germany have shown that the effect of increased potassium contents by autumn application is still measurable in the spring (see chart). In a comparison of spring and autumn fertilisation, the highest K-content in winter rape was measured in the autumn-application variant. However, the test result also showed that this autumn application should be sufficient, as applications of less than 100 kg K2O ha-1 showed only minor increases of the rape plants’ K-content.
As a single, larger supply of potassium may inhibit the uptake of magnesium it is advisable to balance the supply of both nutrients. For this purpose, application of Korn-Kali® with an additional content of 6% water-soluble MgO (as magnesium sulphate), which is readily available to plants. In the Trüstedt field test fertilisation with 160 kg K2O in the form of Korn-Kali® resulted in a marked increase of the potassium content, in comparison with pure potassium fertilisation with 60er Kali®.
Fertilisation recommendation for autumn
The foundation for high yields is set in the autumn. For rape, fertilisation with 300 kg ha-1 Korn-Kali® is advisable, not only to ensure a steady supply of potassium, but also to meet magnesium and sulphur requirements.
For cereals such as winter barley or winter wheat, autumn application of 150 to 200 kg ha-1 of Korn-Kali® will ensure sufficient winter hardiness.
It is very important to make sure that fertilisers are applied prior to the end of the vegetation period, so that plants will have a chance to take up sufficient nutrients. The immediate availability of the water-soluble nutrients in Korn-Kali® is perfect for this process.