Maize is a demanding plant. The main factor determining the amount of grain maize yield is, first of all, balanced pre-sowing fertilization depending on the soil class, its quality and abundance.
Our farms offer several options for pre-sowing maize fertilization. Some of the nutrients are provided in the form of natural fertilizers (manure, slurry, chicken manure). The remaining form of maize fertilization are mineral, multi-component fertilizers, urea, UAN, and saltpeter.
In order to effectively use the yielding potential of maize, its fertilization should be carefully planned - starting with nitrogen. We start by calculating the required nitrogen dose, the date and the choice of the form of the fertilizer used. Nitrogen is the main building block of each plant, it is assumed that with the yield per 1 ton of grain and the appropriate weight of straw, maize plants consume 22-33 kg N. In this case, assuming the yield of 10 tons of grain, we can easily calculate that the demand for nitrogen will be approx. 250 kg/ha.
An important aspect when planning nitrogen fertilization of maize are possible other sources of available nitrogen in the soil - eg from harvest residues, from organic fertilizers, decomposition of organic matter in the soil. The losses caused by washing out, among other things, are equally important. Fertilization of maize with nitrogen for grain or silage is most often performed in spring, due to the high mobility of this type of ingredients in the soil. Sometimes, due to better positions and technical limitations, we can afford one dose of nitrogen before sowing. However, on weaker and lighter soils, think about divided doses. Corn in the initial stage of vegetation absorbs smaller amounts of this nutrient. Therefore, it is recommended to use 50-75% of the recommended dose before sowing maize (ammonium phosphate, urea, UAN, calcium ammonium nitrate, ammonium nitrate). Due to the highest nitrogen utilization at the 4-leaf stage up to 25 days after flowering, it is recommended to apply the rest of the fertilizer for top dressing during 4-6 leaves period.
Most often, nitrogen deficiency causes inhibition of plant growth, and in the initial period, we can observe yellowing of plants. Nitrogen deficiency shortens the growing season and significantly reduces the potential yield obtained. Nitrogen deficiency also reduces the resistance of maize to diseases and other pathogens, and reduces resistance to lodging. Similar symptoms are also shown by the excess of applied nitrogen, where its excessively high doses may also have negative effects on the yield of the obtained grain. Moreover, it causes environmental pollution. Too high doses of nitrogen can cause an increase in green mass or even the formation of too many cobs, which are not able to be fully filled during the growing season. Hence, increasing the amount of nitrogen sown does not make economic sense.
Apart from nitrogen, phosphorus and potassium are very important components that must be supplied to maize during fertilization. The most justified, higher fertilization of maize with phosphorus is in soils with low phosphorus content. The pH of the stand is important, and the lower it is, the more it limits its availability to the plant. It is assumed that with the yield of 1 t of grain and the appropriate weight of straw, maize takes up 11-14 kg of phosphorus. Phosphorus is especially necessary in the fertilization of maize for grain, as it positively influences the setting, formation and maturation of grains in the cob. Phosphorus deficiency causes severe inhibition of plant growth. Very often we see typical symptoms of phosphorus deficiency in cold weather, when the soil temperature is below 12⁰C. Then there is a temporary inhibition of phosphorus uptake by the plant. We can observe limited development of the root system and red-purple discoloration on the leaves. These symptoms and effects of phosphorus deficiency can be eliminated by the use of ad hoc foliar phosphorus fertilizers, which contain an appropriate amount of phosphorus.
Zalecane nawożenie kukurydzy potasem jest dość wysokie, bo ok. 200-300 kg/ha, biorąc pod uwagę to, że plon 1t ziarna kukurydzy pobiera ok. 20-30 kg K20. Potas jest niezbędny przy nawożeniu przedsiewnym kukurydzy ze względu na to, że reguluje on pracę enzymów i produkcję węglowodanów. Potas w głównej mierze jest odpowiedzialny za regulację gospodarki wodnej w roślinie. W razie jego niedoborów utrudnione jest pobieranie wody z gleby. Ostatnie lata dość mocno pokazały nam zróżnicowaną ilość opadów. Podczas suszy rośliny, które zostały optymalnie nawożone potasem, zdecydowanie lepiej poradziły sobie z okresowymi niedoborami wody. Wysokie nawożenie potasem jest racjonalne przy jednoczesnym wysokim nawożeniu azotem, gdyż potas wpływa na zwiększone pobieranie i wykorzystanie azotu. Głównymi wizualnymi objawami niedoboru potasu są chlorozy starszych liści, głównie występujące na końcówkach i brzegach liści. Przy wysokim niedoborze może powodować to zniekształcenie, więdnięcie, a ostatecznie prowadzić do obumierania liści. (BRAK TŁUMACZENIA)
In the fertilization of maize, we also cannot ignore magnesium. Corn takes up about 4-5 kg MgO/ha per 1 ton of grain yield. Recommended fertilization with magnesium is approx. 40-60 kg of magnesium / ha. In the case of a deficiency of this element in the soil, it is easy to supplement it before sowing. On acidic soils, it is worth using calcium-magnesium fertilizers, while on soils with regulated pH, magnesium-sulphate fertilizers can be used. It should be remembered that the amount of magnesium in the soil does not unequivocally affect its availability, but its ratio to potassium. The most optimal ratio of potassium to magnesium in the soil should be 2-3 : 1. All this is due to the fact that a higher ratio worsens the availability of potassium and blocks the uptake of magnesium. The main task of fertilizing maize with magnesium is to increase the efficiency of uptake of nutrients, mainly nitrogen. Magnesium deficiencies are mainly manifested in maize leaf blades. The first symptoms appear on older leaves in the form of white stripes between green veins, which in a very advanced stage of deficiency may lead to necrosis and dieback of the leaves. Magnesium also influences the flowering and pollination of corn cobs. Magnesium deficiencies can also be eliminated by using magnesium as a foliar fertilizer. It is a quick and quite effective solution.
In recent years, we can see reduced sulfur emissions to the environment, caused by pro-ecological assumptions. This resulted in a reduction in the amount of this nutrient in the soil. Moreover, in recent years the use of mineral fertilizers has increased in relation to the use of organic fertilizers, including manure, which contains sufficient amounts of sulfur. Sulfur deficiencies are most often observed on light, sandy, acidic soils. The forecrop was also of great importance as it showed a high demand for sulfur. Sulfur in maize is taken in the amount of 4-5 kg/ha with the yield of 1t of grain and the appropriate weight of straw. Recommended fertilization of maize is from 40 to 50 kg S/ha. Sulfur deficiency leads to inhibition of plant growth, reduction of photosynthesis, i.e. reduction of chlorophyll content. This is manifested by bright spots on younger leaves and visible red discoloration at the edges of the leaf blades. Sulfur significantly affects the use of nitrogen by the plant, which is related to the size and quality of the crop. Similar to magnesium, smaller sulfur deficiencies can be eliminated during foliar fertilization by using magnesium sulphate.
It is very important in the fertilization of maize that it initially uses the food resources that are provided from the seeds of the maize. It is only in the 4-6 leaf phase that the first deficiencies of nutrients appear most often, which the maize is unable to collect or a certain factor prevents its collection from the soil. These deficiencies result from the low fertility of the site or difficult uptake due to weather conditions, pH. In such a situation, it is worth considering which fertilizer to choose for corn and, if possible, apply foliar fertilization in maize, which quickly eliminates the deficiencies of some nutrients.
In recent years, we can see reduced sulfur emissions to the environment, caused by pro-ecological assumptions. This resulted in a reduction in the amount of this nutrient in the soil. Moreover, in recent years the use of mineral fertilizers has increased in relation to the use of organic fertilizers, including manure, which contains sufficient amounts of sulfur. Sulfur deficiencies are most often observed on light, sandy, acidic soils. The forecrop was also of great importance as it showed a high demand for sulfur. Sulfur in maize is taken in the amount of 4-5 kg/ha with the yield of 1t of grain and the appropriate weight of straw. Recommended fertilization of maize is from 40 to 50 kg S/ha. Sulfur deficiency leads to inhibition of plant growth, reduction of photosynthesis, i.e. reduction of chlorophyll content. This is manifested by bright spots on younger leaves and visible red discoloration at the edges of the leaf blades. Sulfur significantly affects the use of nitrogen by the plant, which is related to the size and quality of the crop. Similar to magnesium, smaller sulfur deficiencies can be eliminated during foliar fertilization by using magnesium sulphate.
The boron deficiency can most clearly be observed in the incomplete granulation of the cobs. It is its deficiencies that most often cause disturbances during flowering. This results in irregular fertilization and, as a result, uneven and poor graining, drastically reducing the yield. The demand of maize for the yield of 1t of grain is about 20g B/ha. Due to the low boron content in the soil, unregulated pH of the site, and periodic water shortages, it is important to provide the plant with the necessary amounts of boron in a foliar form. We can start foliar fertilization of maize with boron from the 4-6 leaves stage.
Manganese in maize fertilization intensifies photosynthesis. It affects the right amount of chlorophyll, and thus improves the plant's metabolism. The intake of this component is approx. 35 g Mn/ha per 1 ton of grain. The main factor causing the shortages is too high pH of the site (above 6.5) and drought. The deficiency of this trace element causes marbling of the leaves - at first, bright chlorotic spots between the veins on the blades of fully developed young leaves, to necrosis that can cause dieback. The possibility of preventing a deficiency is maintaining the proper pH of the soil. We can also eliminate deficiencies with maize foliar fertilization.
Agrotechnical errors are the most common cause of iron deficiency in maize. Too high phosphorus fertilization and too little potassium fertilization of maize reduce the uptake of this microelement from the soil. Chlorosis then appears on the youngest maize leaves. Corn takes up 1 tonne of grain from 80 to 100 g Fe/ha. Iron is involved in the synthesis of chlorophyll, carotene and lignin. Participates in the processes of photosynthesis. Iron deficiency in maize can directly reduce the grain yield. Iron cannot be missing in the composition of fertilizers, especially when we choose to fertilize corn for grain.
Copper in maize is taken in small amounts, with the yield of 1t of grain and the appropriate weight of straw is approx. 12g Cu/ha. However, it is worth supplementing it and choosing the appropriate foliar fertilization of maize. Copper plays an important role in the processes of nitrogen transformation, its deficiency can cause fragility of plants and it has a great influence on increasing plant resistance to diseases.
Proper fertilization of maize is a prerequisite for obtaining good-quality, high yields of maize for grain and dry matter. When planning maize fertilization, let us take into account soil fertility studies. This will allow us to properly plan the doses of essential nutrients - macronutrients, and the ability to quickly eliminate micronutrient deficiencies.
We also encourage you to read the article "Which corn fertilizer to choose?".