To obtain high yields, corn fertilizer is required when growing it for any purpose: food, technical, feed. The rate and timing of fertilizing depend on many factors, but in the first place: climate, irrigation, soil structure and fertility.
About nutrients
Corn is a plant with a long growing season. During its course, it consumes a lot of nutrients from the soil. Practice shows that the yield at growing corn for grain and green mass directly depends on the timely application of mineral fertilizers. Corn has been cultivated for a long time and everywhere; in many countries it is called maize.
At different stages of development, nutritional needs are different. During the period of panicle formation, the intensity of consumption increases. When growing modern hybrids, a yield of 1 t/ha is obtained by adding the following minerals:
- nitrogen 24–32 kg;
- potassium 25–35 kg;
- phosphorus 10–14 kg;
- magnesium 6 kg;
- calcium 6 kg;
- boron 11 g;
- copper 14 g;
- sulfur 3 kg;
- manganese 110 g;
- zinc 85 g;
- molybdenum 0.9 g;
- iron 200 g.
The application rate is calculated taking into account the content of basic nutrients (phosphorus, nitrogen, potassium) in the soil. Important periods for the consumption of basic nutrients are considered to be the period of time when 5–7 leaves are formed, and the second - during the growth of 9 and 10 leaves.
First period
During the first period, the reproductive organs are laid down in corn. The number and size of cobs depend on the availability of food; phosphorus is especially necessary at this time. At this time, the crop has a poorly developed root system, so it needs easily accessible forms of nutrients.
A greater need for phosphorus occurs two weeks after the appearance of the first shoots. It is needed for the development of the plant's root system. It is preferable to apply phosphorus fertilizers in the fall. On light sandy soils, any form of nutrition is applied in the spring.
Second period
The duration of the second period is from 17 to 20 days. At this time, intensive growth of the above-ground part of corn occurs, and most of the green mass accumulates. This is when corn needs nitrogen. Weak soil mineralization and leaching of nitrogen from the soil leads to its deficiency.
At this time, nitrogen mixtures are added.Potassium is necessary during the period of ejection of panicles, formation of flowers and ears. In chernozem soils, a deficiency of zinc is noted. When it is deficient, the amount of tryptophan and protein in the plant decreases. Beneficial effects of potassium:
- facilitates nitrogen absorption;
- improves immunity;
- makes the plant resistant to drought;
- influences the formation of cobs.
Types of fertilizers
In different regions, soils differ in structure, and therefore in the content of essential microelements. In the steppe black earth region, corn suffers from a lack of phosphorus and nitrogen. Pre-sowing application is not enough; they are quickly washed out of the soil and by the time flowering begins they are not enough for the full development of plants.
Throughout the season, you need to apply fertilizer to corn. They practice mineral and organic fertilizing. Organic nutrition is a priority. The modern corn fertilization system contains certain standards for applying any type of nutrient mixtures. Today the following proportions of organic matter are applied:
- chernozem lands - from 15 to 20 t/ha;
- soddy-podzolic soils - from 20 to 35 t/ha;
- gray forest lands - from 20 to 35 t/year.
The effect of fertilizers on the yield of a corn field is noticeable. It was noted that the application of manure in a volume of 30 kg can increase the yield by 3–10 c/ha. Manure is used to prepare an infusion; it is needed for watering corn. Infuse it for 3 to 5 days. You need to load 10 kg of mullein into a barrel and add 50 liters of water.
After 5 days the cooking process ends. Before use, mullein infusion is diluted with water: add 1 liter of water to 1 liter of concentrated liquid. There are disadvantages to using a cow:
- long thin stems;
- After watering, a crust forms on the soil.
To eliminate these shortcomings, the application rate is adjusted depending on the composition of the soil. Manure is recommended to be applied to loamy soils at a dose of 30–40 t/ha in the fall for plowing. Organic matter is added to sandy soils in the spring during cultivation.
Liquid manure contains the entire range of microelements that corn needs. Its application rate is 60–80 t/ha. When applying any form of organic fertilizer (liquid, solid), it is distributed evenly over the entire surface of the field with simultaneous incorporation into the ground.
Mineral fertilizers
The use of mineral preparations has a positive effect on the harvest, increases resistance to diseases and bad weather conditions.
Nitrogen
Ammonium nitrate is used as a nitrogen fertilizer. Half the norm (50%) is applied in the spring for plowing; the second half of ammonium nitrate is used in the summer as top dressing. The first time summer feeding is carried out in the phase of the first 5 leaves, the second time - during the formation of cobs.
Nitrogen deficiency is recognized by the color of the leaves. They become thin and lose color: they turn pale and yellow. A sign of deficiency is well eliminated by ammonia. In practice, farmers and summer residents use foliar feeding of corn: ammonia water is used for this purpose.
Violation of nitrogen application standards when fertilizing corn for silage negatively affects its quality:
- the percentage of nitrates in grain increases;
- the percentage of dry matter decreases;
- cobs are formed.
Potash and phosphorus fertilizers
These types of fertilizers applied in the fall to clay soil, and in the spring to sandy soil. Phosphorus is added using special devices during sowing. Superphosphate is a classic phosphorus fertilizer that is applied to the soil. In addition to superphosphate, ammophos is widely used. The rate of application of these fertilizers to the soil is 8–12 kg/ha.
A high level of phosphorus in the soil has positive aspects:
- improves the quality of silage;
- improves cold resistance;
- accelerates the ripening of cobs.
Young plants often suffer from potassium deficiency. They have small shoots covered with dark green leaves, slow growth and the lower surface of the leaves is purple.
Under bad weather conditions (low average daily temperatures), potassium consumption by corn increases. Application of potassium fertilizers reduces stress from cold weather and increases productivity. In cobs, thanks to potassium, the percentage of sugars and starch increases, and their taste improves.
Signs of potassium deficiency:
- wavy edges of leaves;
- dark green color of the leaf blade;
- light leaf tips that turn brown over time.
In the phase of 6–7 leaves, 0.5 kg/ha of potassium fertilizers (potassium salt) is applied to corn. Potassium chloride is added during autumn plowing.
Fertilizer application methods
The entire technology for applying fertilizers to corn is divided into three stages:
- main - fertilizer mixtures are applied during soil preparation in the fall (spring);
- pre-sowing - nutrients are added during sowing;
- fertilizing - during the growing season.
The purpose of basic nutrition is to lay the foundation for adequate nutrition of corn. Fertilizers will be used up as the plants grow. It is recommended to apply fertilizers to the soil in the absence of irrigation for corn in the fall. Minerals added in spring provide a more noticeable increase in yield. Fertilizers must be incorporated into the soil to a depth of 10 cm. At this depth, they are well absorbed by plants.
Among nitrogen fertilizers, preference is given to ammonium fertilizers:
- ammonium nitrate;
- anhydrous ammonia;
- ammonia water.
Phosphorus is supplied using phosphorus flour and superphosphate. The choice of potash fertilizers is wide. Preference should be given to fertilizers that do not contain chlorine: potassium sulfate, magnesium.
Pre-sowing application
Pre-sowing application of fertilizers is carried out during sowing of seeds into the soil. Add small doses of superphosphate or ammophos. By introducing minerals into the row spacing to a depth of 3 cm, high crop yields are achieved. An increase in grain of 3–3.5 c/ha is noted.
When performing dotted sowing, corn is fed with superphosphate granules. Productivity increases by 4 c/ha with additional addition of small doses of potassium and nitrogen to the soil. The use of mineral fertilizers on fertile soils does not give such a noticeable effect.
The effectiveness of complex fertilizers for corn has been proven in practice. In the spring, before sowing, nitrophoska, diamofoss, and sulfoammophos are applied. Many agricultural enterprises use it for feeding corn. liquid complex fertilizers. UAN, a urea-ammonium mixture, is in demand. Liquid fertilizers are good because they can be applied to the soil using special equipment.
Summer feeding
On poor soils and in the absence of basic nutrition, fertilizers become the main suppliers of nutrients. Nitrogen and phosphorus are applied to a depth of 6–8 cm. For their better absorption, the soil should contain a small amount of moisture. With the help of summer fertilizing, a yield increase of 3–5 c/ha is achieved.
Leaf feeding
Foliar feeding is the fastest way to deliver nitrogen to the plant. Spraying on the leaf can be carried out in the absence of symptoms of nitrogen deficiency. Carbamide (urea) is used to prepare the fertilizer mixture. Treatment with urea is combined with pesticides.For foliar feeding, urea is considered the best.
The digestibility of amide nitrogen is 90–95%. Nitrogen absorption occurs in an extremely short time.
Weather requirements during work: calm, air temperature not lower than 20 °C. Magnesium and sulfur are added to the fertilizer mixture with urea. They are well absorbed through corn leaves. The concentration of active substances in the solution should not exceed 5%.
Stronger doses may cause leaf burns. Up to 250 liters of solution are consumed per hectare. Foliar feeding with fertilizers containing copper and zinc, if a low content of these minerals is detected in the soil. Treatment is carried out in the 6-leaf phase.
Conclusion
When growing corn, there is a need to use all types of fertilizers. The developed systems differ little when growing crops for grain or silage. Good results are achieved by using optimal doses of fertilizers.
