Fertilizers for corn

Corn nutrition and yield are interrelated. Proper application of nutrients ensures intensive crop growth and fruiting. The degree of assimilation of trace elements depends on the structure, temperature, soil moisture, its pH.

What Nutrients Does Corn Need?

At different phases of development, the needs of corn for nutrients change. This must be taken into account when drawing up a feeding scheme. Active consumption of nitrogen (N) by corn begins in the phase of 6-8 leaves.

Before their appearance, the plant absorbs only 3% of nitrogen, from the appearance of 8 leaves to drying on the cobs of hair – 85%, the remaining 10-12% – in the maturation phase. The yield of corn, the volume of biomass depends on nitrogen.

Potassium (K) also affects yield:

• improves the consumption and use of moisture;
• potassium top dressing contributes to good cob graining;
• increases the drought tolerance of corn.

Corn experiences the greatest need for potassium in the flowering phase. Phosphorus (P) culture needs less than nitrogen and potassium. This can be assessed in terms of the digestibility of nutrients. With a productivity of 80 c/ha, the ratio N: P: K is 1: 0,34: 1,2.

Nutrient P (phosphorus) corn is needed in 2 phases:

• at the initial stage of growth;
• during the period when generative organs are formed.

It participates in the formation of the root system, has a direct effect on energy metabolism, promotes the accumulation and synthesis of carbohydrates, and participates in the processes of photosynthesis and respiration.

For the full absorption of the NPK complex, corn needs calcium. With its lack, soil parameters deteriorate (physical, physico-chemical, biological):

• there is an increase in specific gravity;
• the structure is changing for the worse;
• buffering deteriorates;
• the level of mineral nutrition is reduced.

The lack of magnesium (Mg) in the soil is manifested by low yields, its deficiency affects the processes of flowering, pollination, grain cobs and their number.

Sulfur (S) affects the strength of growth and the degree of nitrogen assimilation. Its deficiency is manifested by a change in the color of the leaves. They become light green or yellow. With this in mind, it is necessary to carry out top dressing of corn growing in the country or in the field. At the same time, it is necessary to remember the role of microelements on the maize enzymatic system.

Culture during the growing season needs zinc, boron, copper:

• copper increases the percentage of sugar and protein in grains, affects yield and immunity;
• with a lack of boron, growth slows down, flowering and pollination worsen, internodes are reduced at the stems, the cobs are deformed;
• zinc for corn is in the first place, it is involved in metabolic processes, growth strength and frost resistance depend on it, with its deficiency, cobs may be absent.

Types of fertilizers and application rates

The minimum amounts of fertilizer for corn are calculated from the expected yield. When calculating, they proceed from the need of the culture for the main nutrients.

The rates are given for a plot of 100 x 100 m, if corn is grown on an area of ​​1 weave (10 x 10 m), all values ​​are divided by 10.

Organic

In the open ground in the country, in the field, liquid manure is traditionally used to feed corn. Recipe for infusion for root dressing:

• water – 50 l;
• fresh mullein – 10 kg;
• insist 5 days.

When watering for every 10 liters of irrigation water, add 2 liters of liquid manure.

Mineral

According to the presence of nutrients in them, all mineral fertilizers are divided into simple, containing one nutrient element, and complex (multicomponent).

For feeding corn, simple forms of mineral fertilizers are used:

• nitrogen;
• phosphoric;
• potassium.

potassium and phosphorus

For feeding corn, highly concentrated forms of fertilizers are chosen. Of the phosphate preparations, preference is given to:

• superphosphate;
• double superphosphate;
• phosphorus flour;
• but

With a yield of 1 t/ha, the rate of potash fertilizers is 25-30 kg/ha. Potassium salt, potassium chloride are added under corn (in autumn).

Nitrogen

Fertilizers can contain nitrogen in amide (NH2), ammonium (NH4), nitrate (NO3) forms. The root system of corn assimilates the nitrate form – it is mobile, easily absorbed at low soil temperatures. The amide form of nitrogen is absorbed by the plant through its leaves. The transition of nitrogen from the amide form to the nitrate form takes from 1 to 4 days, from NH4 to NO3 – from 7 to 40 days.

Feeding corn with urea per sheet

The intensity of nitrogen assimilation increases by the time 6-8 leaves appear. This is in the second half of June. The need for nitrogen does not decrease until the hair dries on the cob. Foliar top dressing with a solution of carbamide to corn is carried out in 2 stages:

• in the phase of 5-8 leaves;
• during bud formation.

On industrial fields, nitrogen norms are 30-60 kg/ha. When growing corn on a small scale, use a 4% solution:

• water – 100 l;
• urea – 4 kg.

In ripe corn grains, the protein content increases to 22% when foliar feeding with carbamide. For the treatment of 1 ha, 250 liters of a 4% solution are required.

Fertilizing corn with ammonium nitrate

Foliar top dressing with ammonium nitrate is carried out when symptoms of nitrogen starvation appear. Deficiency is manifested by thin stems, discoloration of leaf plates. They turn yellow-green. Norm for corn:

• water – 10 l;
• ammonium nitrate – 500 g.

Terms and methods of feeding

Nutrients are needed by the culture throughout the growing season. Applying the entire rate of fertilizer at one time does not bring benefits. Changes in the feeding scheme affect the yield, the quality of the ears.

In the traditional nutrition system, there are 3 terms for applying mineral fertilizers:

• the main part is paid before the start of the sowing period;
• the second part is brought in the sowing period;
• the rest of the mineral nutrition is added after the sowing period.

Fertilizers before sowing corn

Organics (manure) and the required volume of phosphorus-potassium fertilizers are planted in clay soils in the fall (during autumn cultivation). In sandy and sandy soils, manure is applied in the spring. During spring cultivation, nitrogen is replenished, ammonium nitrate, ammonium sulfate, ammonia water are used.

Ammonium sulfate contains sulfur, necessary for the synthesis of proteins, as well as ammonium (NH4). It is used as the main fertilizer for pre-sowing spring feeding of corn. The recommended rate of fertilizer is 100-120 kg/ha.

Fertilizers when planting grains

When sowing, fertilizers containing phosphorus and potassium are applied. From phosphate fertilizers, preference is given to superphosphate and ammophos. They are applied at the rate of 10 kg/ha. The action of ammophos manifests itself faster. In its composition: phosphorus – 52%, ammonia – 12%.

Granules are applied to a depth of 3 cm. Exceeding the recommended norms leads to a decrease in yield. Ammonium nitrate is considered the best nitrogen fertilizer. It is applied to the soil when sowing corn. The recommended application rate is 7-10 kg/ha.

Top dressing of corn after the appearance of leaves

When the crop is in the 3-7 leaf phase, the fertilizer is applied to the soil. Initially, organics are added:

• manure slurry − 3 t/ha;
• chicken manure – 4 t/ha.

The second top dressing is carried out with superphosphate (1 centner/ha) and potassium salt (700 kg/ha). For 3 weeks from the appearance of the 7th leaf, root dressing with urea is carried out. Corn is sprayed in calm weather, the optimum air temperature is 10-20 ° C.

In the industrial cultivation of corn, top dressing with UAN is practiced – a urea-ammonia mixture. This fertilizer during the growing season is used twice:

• before the appearance of the 4th leaf;
• before closing the leaves.

Plantings of corn are watered with a liquid solution of UAN in the amount of 89-162 l/ha.

In the early stages of growth, corn may develop symptoms of zinc deficiency:

• growth retardation;
• yellowish color of young leaves;
• white-yellow stripes;
• short internodes;
• withered lower leaves.

Zinc deficiency affects carbohydrate metabolism and affects the quality of cobs.

When symptoms of starvation appear, foliar feeding is carried out. Use zinc fertilizers:

• NANIT Zn;
• ADOB Zn II IDHA;
• zinc sulfate.

During the period of drought, corn is fed with potassium humate. This allows you to increase the yield by 3 q/ha. Under conditions of normal humidity, this figure rises to 5-10 c/ha. Foliar top dressing is carried out in the phase of the 3-5th and 6-9th sheets.

Advantages and disadvantages of fertilizers

When choosing a fertilizer, it is necessary to take into account its positive and negative effects on the soil, especially the application.

Conclusion

Properly organized top dressing of corn is necessary throughout the warm season. It consists of main and corrective actions. The choice of fertilizers, the application rate, is determined by the climatic conditions of the region, the composition and structure of the soil.