WHEN TO APPLY FERTILIZER TO WINTER WHEAT?
Before sowing wheat, the soil must be prepared. The first step is to lime the field. Then it is fertilized with potassium and phosphorus fertilizers. Spring fertilization of wheat should consist of applying three doses of nitrogen fertilizer. It is also important not to forget about the foliar application of microelements to the plant.
Fertilization with phosphorus and potassium for winter wheat
Phosphorus and potassium contribute to better wintering and increased resistance to diseases in winter wheat. Phosphorus ensures proper development of the root system, which translates into better absorption of water and nutrients from the soil by the plant. This mineral also helps winter wheat regenerate much faster after winter. It also improves nitrogen uptake from the soil and increases grain filling.
Potassium also helps winter wheat to better absorb nitrogen and supports it in wintering. Additionally, it affects the plant’s water economy, helping it retain water in cells, which is crucial, especially during drought.
Phosphorus and potassium deficiencies lead to a reduction in the root system, which is very unfavorable for plants, especially during drought. Wheat bushes are less, have lower quality, and have smaller grain mass. Additionally, plants winter worse and are more susceptible to fungal diseases.
Phosphorus and potassium should be applied to the soil in autumn. Fertilization will bring the best results when applied before plowing and mixed with a layer of soil 10-20 cm thick. These elements should be in the soil 7-14 days before sowing wheat. It is good practice to apply the entire dose of phosphorus pre-sowing. Potassium, due to its easy movement in the soil and faster leaching on lighter soils, is recommended to be applied in two doses – the first dose (comprising ⅔ of the recommended fertilizer portion) is applied pre-sowing, and the rest of the potassium is applied in early spring.
Jesienią w fazie 3–4 liściom pszenicy ozimej podaje się nawóz mikroelementowy, zawierający m.in. miedź, żelazo, mangan, molibden, bor i cynk. Dzięki temu roślina będzie lepiej się ukorzeniać. Drugą dawkę nawozu dolistnego należy podać wiosną, na początku krzewienia. Powinien się w niej znaleźć nawóz mikroelementowy połączony z fosforowym. Trzecia dawka jest aplikowana w fazie strzelania w źdźbło. Na tym etapie ponownie trzeba podać nawóz mikroelementowy w połączeniu z nawozem fosforowym. Czwartą dawkę środka powinno się podać w fazie kłoszenia. Należy wtedy zastosować skoncentrowany nawóz fosforowo-potasowy. Nawożenie dolistne zbiega się w czasie z podawaniem środków ochrony roślin m.in. przeciw fungicydowych.
Foliar fertilization of winter wheat
In autumn, when winter wheat has 3 to 4 leaves, a microelement fertilizer containing copper, iron, manganese, molybdenum, boron, and zinc is applied. This helps the plant to root better. The second dose of foliar fertilizer should be applied in spring, at the beginning of tillering. It should contain microelement fertilizer combined with phosphorus. The third dose is applied at the stem elongation stage. At this stage, microelement fertilizer combined with phosphorus should be applied again. The fourth dose of the agent should be applied at the heading stage. A concentrated phosphorus-potassium fertilizer should be used at this stage. Foliar fertilization coincides with the application of plant protection products, including fungicides.
LIMING WINTER WHEAT
Winter wheat grows best on soil with a pH ranging from 5.5 to 7.5. If the pH is 5.5 or less, a liming of the cultivated field is necessary. Soil liming for winter wheat is best done in autumn. It is important to remember to allow a minimum of 6 weeks between lime application and the sowing of phosphorus fertilizers. Calcium deficiency in the soil and its acidification inhibit the proper development of plants and limit the absorption of nutrients. If, in addition to calcium deficiency, there is a magnesium deficiency, it is necessary to use magnesium lime. The deficiency of these two elements also prevents plants from developing proper roots.
A good solution for autumn liming of soil for winter wheat is to use products such as granulated lime Polcalc III Generation or SuperMag if there are also magnesium deficiencies. The lime dose will vary depending on how much the soil pH needs to be raised. For example, if it needs to be raised by 0.7-1.3, 500 to 700 kg of lime per hectare should be used. The highest dose that can be used (and is economically viable) is 1000 kg of lime per hectare – such an amount is applied to strongly acidic soil.
WHAT FERTILIZER TO APPLY TO WINTER WHEAT IN SPRING?
Nitrogen is an essential element for winter wheat. It is particularly important when spring vegetation begins. It affects the proper growth and development of plants, as well as their good yields.
Fertilization with nitrogen for winter wheat
Winter wheat fields are fertilized with nitrogen in three doses. The first dose is applied early in spring. At this time, 30 to 60/80 kg of nitrogen per hectare is applied. If winter wheat has a dark green color, is dense, and well-branched, a smaller amount of the preparation can be applied. If it was sown late, a larger dose would be necessary.
After the initial dose, the second dose is applied, ranging from 40 to 60 kg of nitrogen per hectare. This is the moment when the first node can be felt, and winter wheat begins to elongate.
The third dose is applied with about 60 kg of nitrogen per hectare. This occurs when the plant is just before heading, until the stage before the leaf sheath opens.
As for autumn nitrogen fertilization, it is not necessary, as winter wheat does not absorb large amounts of this element during this time. Autumn nitrogen application is a required procedure only when wheat is sown after other cereals. In such cases, 20 to 30 kg of nitrogen per hectare is applied. It can be applied in autumn in the form of ammonium or amid. Nitrogen in the form of nitrate reduces the plant’s chances of surviving the winter. If winter wheat is sown after rapeseed, sugar beet, or leguminous plants, there is no need to apply nitrogen before sowing.
WHAT FERTILIZER RATES TO USE FOR WINTER WHEAT?
Proper growth of winter wheat depends on the selection of appropriate doses of fertilizers with micro and macro elements.
Nutritional requirements of winter wheat
Winter wheat is sown on the best soils due to its high requirements. According to recommendations, it should be grown on soils of the following complexes:
- very good wheat complex;
- very good rye complex;
- mountain wheat and mountain grain complexes;
- strong grain-pasture complex.
Winter wheat has high nutritional requirements. Assuming that 8 tons are produced per hectare, winter wheat will take from the soil: 184 kg of nitrogen, 80 kg of phosphorus pentoxide, 160 kg of potassium oxide, 40 kg of magnesium oxide, and 40 kg of calcium oxide.
