The most important source of nitrogen in plant nutrition, first of all, is the soil itself.. The provision of plants with soil nitrogen in the specific conditions of different soil and climatic zones varies. In this regard, there is a tendency to an increase in the resources of soil nitrogen in the direction from the poorer soils of the podzol zone to relatively powerful and ordinary black soils provided with nitrogen. Light sandy and sandy sandy soils are extremely poor in nitrogen.
The main reserves of nitrogen in the soil are concentrated in its humus, containing about 5% nitrogen. Therefore, the higher the content of humus in the soil and the more powerful the layer of soil impregnated with it, the better the provision of the crop with nitrogen. Humus is a very resistant substance, and its decomposition by microorganisms with the release of mineral salts is extremely slow. Therefore, only about 1% of the nitrogen in the soil of its total content appears to be water-soluble mineral compounds available to plants.
nitrogen cycle in nature
Soil organic nitrogen is available to plants only after its mineralization. - the process carried out by soil microorganisms using the organic matter of the soil as an energy source. The intensity of mineralization of organic nitrogen also depends on the physicochemical properties of the soil, conditions of humidity, temperature, aeration, etc.
Nitrogen can also come from the atmosphere with precipitation and directly from the air, with the help of so-called nitrogen fixers: some bacteria, fungi and algae. But this nitrogen is relatively small, and it can play a role in nitrogen nutrition as a result of accumulation over long years on non-arable and virgin lands.
Nitrogen in plant life
Not all organic substances of plants contain nitrogen in their composition. It is not, for example, in the most common compound - fiber, it is absent in sugars, starch, oils, which the plant synthesizes. But in the composition of amino acids and proteins formed from them there is necessarily nitrogen. It also enters nucleic acids, the second most important substances of any living cell, which are of particular importance for the construction of proteins and carry the hereditary characteristics of the organism. Live catalysts - enzymes - also protein bodies. Nitrogen is found in chlorophyll, without which plants cannot absorb solar energy. Nitrogen enters lipids, alkaloids and many other organic compounds that occur in plants.
From vegetative organs Most of the nitrogen is young leaves, but as the nitrogen ages it moves into the newly emerging young leaves and shoots. Later, after pollination of flowers and the setting of fruits, there is a more and more pronounced movement of nitrogen compounds into the reproductive organs, where they accumulate in the form of proteins. By the time of seed ripening, the vegetative organs are significantly depleted in nitrogen.
But if plants get excess nitrogen nutrition, it accumulates a lot in all organs, while there is a rapid development of the vegetative mass, which delays maturation and can reduce the proportion of desired products in the total yield of the cultivated crop.
Normal nitrogen nutrition not only increases the yield, but also improves its quality. This results in an increase in the percentage of protein and the content of more valuable proteins.
Cultures normally provided with nitrogen grow rapidly, their leaves are distinguished by an intense dark green color and large size. On the contrary, the lack of nitrogen retards the growth of all organs of the plant, the leaves have a light green color (there is little chlorophyll, which is not formed due to the weak supply of the plant with nitrogen) and are often small. Crop falls, the content of proteins decreases in seeds. Therefore, with a lack of organic nitrogen in the soil, the need to ensure normal nitrogen nutrition of plants with fertilizers is a very important task for agriculture.
Nitrogen fertilizer application and application rates
When applying nitrogen fertilizer increases the yield of almost all crops. Nitrogen fertilizers in agriculture and horticulture are used everywhere: for vegetable crops, for potatoes, beets, tomatoes, cucumbers, for fruit crops, fruit trees, shrubs, grapes, strawberries, strawberries, ornamental plants, flowers (roses, peonies, tulips and others), also used for seedlings and lawns.
The exception can be considered legumes (peas, beans, etc.), generally less in need of nitrogen.
- For gardens and gardens, the average dose for the main application for potatoes, vegetable, fruit and berry and flower crops should be considered 0.6-0.9 kg of nitrogen per 100 m².
- When feeding for potatoes, vegetable and flower crops - 0.15-0.2 kg of nitrogen per 100 m²., For fruit crops - 0.2 - 0.3 kg of nitrogen per 100 m².
- To prepare the solution, 15-30 g of nitrogen are taken per 10 liters of water with the solution distributed over 10².
- For foliar application, 0.25-5% solutions are used (25-50 g per 10 l of water) with a distribution of 100-200 m².
All values are given without taking into account the percentage of nitrogen in each type of fertilizer, for conversion to fertilizers, it is necessary to divide by the percentage of nitrogen in the fertilizer and multiply by 100.
Nitrogen fertilizers include mineral and organic fertilizers, first consider mineral nitrogen fertilizers.
Types of mineral nitrogen fertilizers
The entire range of production of nitrogen fertilizers can be combined into 3 groups:
- Ammonium fertilizers (for example, ammonium sulfate, ammonium chloride),
- Nitrate fertilizers (for example, calcium or sodium nitrate),
- Amide fertilizers (for example, urea).
In addition, fertilizers are produced that contain nitrogen in both ammonium and nitrate forms (for example, ammonium nitrate).
The main range of production of nitrogen fertilizers:
Effect of nitrogen on plant growth and development
There is a direct relationship between the lush, dark green foliage of a plant and the amount of nitrogen it needs. And this relationship is photosynthesis.. Chlorophyll plays an important role in the process of plant photosynthesis. That nitrogen is the main component of the protein, which is involved in the formation of chlorophyll.
The nitrogen reserve is contained in the soil (humus), accounting for about 5%, depending on the climatic zone. The most nutritious soil is the one where there is more humus. But even if the soil is very rich and fertile, only 1% of nitrogen will be available to the plant. This is due to the fact that the process of decomposition of humus and the release of mineral salts is very slow. At the same time in spring, during the period of active growth and development, garden crops most in need of nitrogen. Its deficiency can lead to a slowdown in the growth and development of horticultural crops. To prevent such a situation and to guarantee the correct growth of plants, it is necessary to provide them with additional nitrogen fertilization.
Types of Nitrogen Fertilizers
Organic fertilizerwhich will contain nitrogen can be obtained independently using a compost pit and plant waste. In such plants as clover and lupine, 0.4 - 0.7% of nitrogen is contained, and in green foliage - 1%, in bird droppings (chicken, pigeon, duck) and manure.
But before the nitrogen in the organic fertilizer goes into the mineral form, which will be available for plant nutrition, it will take time. If it is necessary to feed more quickly, you should use industrial-made nitrogen fertilizer. The popularity of industrial mineral fertilizers due to their effectiveness, ease of use. There are several main groups:
- nitrate fertilizers: sodium nitrate, calcium nitrate,
- ammonium fertilizers: ammonium chloride, and ammonium sulfate,
- ammonium nitrate fertilizers: a complex group of nitrogen-containing supplements, such as ammonium nitrate,
- amide fertilizers: urea,
- liquid fertilizers: ammonia anhydrous and ammonia water.
Sodium nitrate (sodium nitrate)
Grayish or yellowish powder, easily soluble in water and containing 16% nitrogen. Sodium nitrate is produced by crystallization using natural deposits or ammonia of synthetic origin. Sodium Nitrate - alkaline fertilizer, so it is more efficient to use it on acidic soils.
Do not use on soils oversaturated with sodium. It should be used during planting and fertilizing, quickly absorbed by plants. Sodium nitrate is actively used during spring dressings of beets, potatoes, fruit and berry, ornamental crops. It is desirable to exclude use in the fall, as there is a probability of leaching of nitrogen from the soil. When storing is not caking.
Calcium nitrate (calcium nitrate)
Available in large pearl-colored granules or in crystalline form. The granulated form is more popular because it is not sprayed during use. In nitrate form, contains 15-17% nitrogen. As part of calcium nitrate - calcium - 19% and nitrogen - 13%. Calcium nitrate, while following the recommendations and dosages, has a positive effect on yield and does not adversely affect humans. Despite the fact that nitrate contains nitrogen, it does not oxidize the soil, so it is used on different types of soil. With regular use - improves the properties of acidic soil.
Calcium, which is part of calcium nitrate, ensures the full absorption of nitrogen, contributing to the development and growth of culture. Calcium accelerates the germination of seeds and tubers, increases plant immunity and winter hardiness, strengthens the stands and the root system.
Ammonium sulphate (ammonium sulphate)
Available in white or gray crystalline form, it is easily dissolved in water. Contains about 20.5% of nitrogen and is suitable both for fertilizing and for the main application. Contains ammonia nitrogen, which is fixed in the soil, so the most suitable soil is light, permeable. It should not be used on neutral and weakly acid soils, since ammonium sulphate has the property of acidifying the soil. It is optimal for dressing heathers, rhododendrons and other inhabitants on acidic soils. When storing is not caking.
Available in white granular form with a nitrogen content of about 35%. It is used both as an auxiliary feeding, and as a basic fertilizer. Saltpeter is less effective on very moist soil, as it is a non-balancing substance and can leach into groundwater. Therefore, mainly its territory of use - soil with low humidity. Ammonium nitrate with regular use increases the acidity of the earth, to prevent this, use neutralizing agents.
Store fertilizer in a dry place, as it tends to absorb moisture and clog. If before use it was found that saltpeter was formed into large stones, then they should be broken to evenly distribute the top dressing.
Currently, pure saltpeter is practically not available for sale, it is mainly included in the mixture. The most suitable mixture will be one where the content of ammonium nitrate does not exceed 60%, while the neutralizing substance is 40%. This ratio of feeding contains in its composition 20% nitrogen.
Concentrated fertilizer with a nitrogen content in the amide form of about 46% and is easily soluble in water. The use of urea for additional feeding during the warm period of the year on neutral soils is more efficient. Because the nitrogen contained in urea is poorly absorbed by plants, since it is necessary that it passes into the mineral form, and the transition process depends on the temperature and acidity of the soil.
Fertilizer is used for foliar feeding.due to the gentle effect on the leaves of the plant. And also used for spring application before planting. It is desirable to use urea in liquid form, this method will allow the fertilizer to be evenly distributed in the soil, in case of a high concentration of nitrogen burns are possible in the plant.
Liquid ammonia is distinguished by two types.: in the first, the ammonia content is 20-25%, in the second - 16-20%. The nitrogen content is 82%. In the process of fertilizer requires embedding in the ground by 8 cm, otherwise it will evaporate. Liquid fertilizers have several advantages:
- low cost,
- plants absorb liquid fertilizer well,
- uniform distribution over the entire area to be treated,
- longer duration of exposure.
But many gardeners and gardeners are stopped by such moments as:
- transportation and storage (it is not recommended to store at home),
- liquid fertilizers burn leaves,
- fertilization process requires special equipment.
In the spring, during the period of active growth, the plant needs not only nitrogen, which contributes to the formation of foliage, but also other substances and components that help growth and development. Namely:
- phosphorus helps the plant with the ovary, increases the winter resistance of the culture,
- Potassium improves immunity, thus plants are more resistant to various diseases and negative natural phenomena.
Each plant has its own needs
It is necessary to understand which crops require a high nitrogen content in the soil, and which should not. When nitrogen deficiency plant slows growth, and the foliage turns yellow. Providing the right dose feeding, we help the plant to develop properly, to form healthy foliage, and also to accumulate the necessary amount of protein in the fruit.
But if you overuse these fertilizers and exceed the needs of the crop, then all the forces of the plant will go to the foliage, which will have a negative effect on flowering, ovary and fruit ripening. Too much nitrogen causes foliage burns. In the future, the death of the foliage and then the root system itself.
So, garden and garden crops are divided into four groups, each of which needs its own, certain amount of nitrogen.
First group. This group is characterized by a high demand for nitrogen both before planting (sowing) and during the growing season. The recommended dose is at least 25g. ammonium nitrate, taking into account the area of landings - 1 square. If it is planned to use other types of fertilizer, their amount should be adjusted, taking into account the nitrogen content. The first group of cultures include:
- fruit trees and shrubs: plum, blackberry, raspberry, cherry, strawberry,
- vegetable: pumpkin, pepper, rhubarb, zucchini, eggplant, potatoes, cabbage,
- decorative cultures: peony, balsam, rose, dahlia, nasturtium, carnation, lilac, phlox paniculata and others.
Second group. Cultures in this group require an average nitrogen content. The recommended dosage for nutrition is 20 grams. ammonium nitrate per 1 square. m. landing area. The group includes:
- fruit and berry crops: currant, apple, gooseberry,
- vegetable: beet, tomato, cucumber, garlic, carrot, parsley, corn,
- decorative: most of the annual flowers, delphiniums.
Third group . Moderate nitrogen requirements are typical for this group. Recommended 15 grams. ammonium nitrate per 1 square. m. landings. The cultures of the third group include:
- fruit trees: pear,
- vegetable: radishes, onions, early potatoes,
- ornamental: bulbous species, saxifrage, daisy, juniper, primula.
Fourth group . Plants in the group require a minimum nitrogen content, namely 7-8 grams. nitre per 1 square. m. landings. The fourth group of cultures include:
- vegetable: beans, aromatic herbs, peas,
- ornamental: Japanese azalea, young, rhododendron, heather, purslane, Erica, Oriental poppy and others.
Basic rules in the application of nitrogen fertilizers
The correct dosage and regular timely use of nitrogen fertilizers favorably influences the development and growth of garden and garden crops. The required amount of fertilizer is calculated based on the soil, the plant itself and the season. But there are also basic rules for the use of fertilizers:
- A favorable period for applying nitrogen fertilizer is considered to be early spring. In the autumn, there is a high risk of nitrogen leaching by groundwater,
- fractional introduction of the component - the key to a positive result,
- when using nitrogen fertilizers on acidic soils, you must first mix them with lime and chalk, ensuring rapid absorption by plants,
- the use of nitrogen-containing fertilizers favorably affects dry soils in the area of forest-steppe and steppe,
- it is desirable to fertilize the chernozem after ten days
- To ensure good nutrition, complex fertilizers are recommended.
A plant that consumes the necessary rate of nitrogen is well developed and has healthy foliage of dark green color. As well as a balanced and regular nitrogen nutrition contributes to a high quality crop.
Fertilizers in liquid form
Anhydrous ammonia. This is the most concentrated substance, which contains no ballast substances. It has no color, it actively reacts to the surrounding temperature, therefore it needs special storage conditions. During production, it is sealed in an airtight container, as the liquid is pumped under pressure due to which it is divided into two forms - liquid and gaseous.Quite aggressive to certain types of metals and alloys, it is not recommended to be stored in zinc and copper vessels. Because of the high concentration of ammonia, the fertilizer is toxic, and you must take precautions when working with it. Well absorbed by plants.
It can be used as a fertilizer in the fall, but on the lands of light grain size it is distinguished by rapid vymyvaemosti. That is why the agrochemical in such cases is shown to be deeply introduced into the ground in the spring.
The introduction of waterless ammonia
Video - Fertilizing soil with anhydrous ammonia
Ammonia water. Fertilizer is sealed in special containers that are under pressure. The substance is not aggressive to metals, contains a volatile formula of free ammonia, which contributes to a large loss of nitrogen during application to the soil. It can be used for autumn, spring introduction or as top dressing. It is brought along with water into the deep layers of the soil - by 12-15 cm.
Ammonia water - for increased yields and cost savings
Ammonia The nitrogen content of these liquid chemicals can vary from 30 to 50%. Substances are obtained by dissolving various dry granular nitrogen fertilizers in water: ammonium nitrate, urea, etc. These are rather aggressive substances that cause corrosion of ferrous metals and copper alloys.
Ammonia - soil application
Ammonia types of dry agrochemicals
Ammonium nitrate. It is used as the main fertilizer or in the form of top dressing. The composition of the agrochemical does not contain ballast substances, is well soluble in water, can be used on dry and overmoistened soils. At increased humidity, it is washed away from the upper layers of the soil. To prevent an overdose on a certain piece of land, it needs additional shredding before it is applied, since it tends to be caked. It can be used together with superphosphates, but the mixture must be enriched with neutralizing components (lime, dolomite, chalk). The content of the neutralizer should not exceed 15% of the total mass of fertilizers.
Rarely sold in its pure form, most often in the form of a mixture with a neutralizer.
Ammonium sulfate. Nitrogen in this type of agrochemical is presented in the form of a cation, which tends to linger in the soil. Fertilizer is well absorbed by plants, as it is not washed away by precipitation and melting of snow in the lower layers of the soil. It can be applied to entering into the earth during the autumn and winter period. Has an acidifying effect on the fertile layer, it is recommended to mix in half with a neutralizer. It can be applied as the main fertilizer or in the form of top dressing. Sold in a clean and diluted form with a neutralizer.
Ammonium chloride. This type of fertilizer is recommended to be used only in the autumn-winter period. It's all about the large content of chlorine in the formula of agrochemical. Chlorine has a negative effect on plant growth and development. The fertilizer applied for the winter is decomposed, chlorine is lowered along with precipitation into the lower layers of the soil.
Ammonium chloride (chloride)
Nitrogen fertilization rates
Nitrate types of dry agrochemicals
Calcium nitrate. This type of agrochemical is used as the main fertilizer. It has an alkaline composition, suitable for various types of soil. Well absorbed by plants, but has a low fixability in the soil. It helps to reduce the acidity of the soil, so the best result is shown on acidic types of soil.
Sodium nitrate. It is also effective on acidic soils, well absorbed by plants, most of all suitable for root crops, as it increases the outflow of carbohydrates from the leaves to the roots. It is not applied for winter, as it is quickly washed out of the soil due to its low fixability.
Amide type dry agrochemicals
Urea. It has the highest concentration of nitrogen, can be used as a basic fertilizer and as a top dressing. It is introduced into the soil in spring, as it is highly washable. When feeding, it is quickly absorbed by plants: 2 days after application, an increase in nitrogen is observed in protein compounds.
Organic Nitrogen Fertilizers
Bird droppings. It is impossible to call this type of fertilizer effective for large areas. The nitrogen content in bird droppings ranges from 1 to 2.5%. Also worth noting is that this type of fertilizer is considered toxic.
Compost. In homemade fertilizer, nitrogen is also contained in small quantities - up to 2%, but the compost itself is quite a nutritious and useful mass for the growth of most plants, therefore its use as a top dressing or base for planting is quite popular and common.
What is this fertilizer for?
During growth and development, the plant synthesizes many different proteins, differing in functionality, molecular weight and number of amino acids. Those proteins that are produced during different stages of plant growth differ significantly from those substances that make up the organs and cells of the already formed shoots and leaves. It should be noted that any protein synthesis is accompanied by a large loss of energy, which is formed in the process of photosynthesis.
It is nitrogen that provokes the process of photosynthesis in plants, which in turn contributes to more rapid and high-quality protein synthesis. Especially important is the presence of nitrogenous fertilizers in the soil at a time when the plants form stems and leaves. In the process of development, the plant actively absorbs nitrogen from the soil and accumulates it in its organs. As the plant grows, nitrogen can pass from aged organs to newly formed shoots and leaves.
Nitrogen in plant life. Nitrogen fertilizers
After being applied to the earth, nitrogen fertilizers are processed by almost 70% by various microorganisms inhabiting the soil. Also, the leaching of salts and nitrates from the upper layers of the soil. After the death of bacteria, the plants begin to absorb the necessary nitrogen from the formed mass. The share of plants is no more than 40-50% nitrogen from the total fertilizer applied.
How to understand that plants lack nitrogen
Lack of nitrogen catastrophically affects the growth and development of any vegetable crops. First of all, the process of photosynthesis and respiration slows down, which provokes growth retardation and the formation of shoots and leaves. Also, lack of nitrogen can cause changes in the shape of the leaves, reduce the size of inflorescences, the lack of fruit formation. If plants are deficient in nitrogen, their leaves change color, become pale, in particularly difficult cases, chlorosis can be observed.
Signs of nitrogen deficiency
The most common lack of nitrogen is observed on the following types of soil:
- red soils
- high alkali content.
It is also worth knowing that nitrogen starvation can occur in the following cases:
- spring fertilizer is applied to the soil too early and microorganisms that contribute to nitrogen mineralization, do not process nitrogen-containing chemicals,
- nitrogen starvation can occur in carbon black soil,
- a large amount of precipitation in the spring. Excessive moisture helps flush out nitrogen from topsoil.
Soil type and nitrogen saturation
The climatic conditions of the regions affect the richness of the soil with nitrogen. The amount of nitrogen in the soil type is arranged in descending order:
- Chernozem, powerful and ordinary.
- Podzolic soil.
- Sandy, sandy soil.
Most of the nitrogen (about 5%) is contained in the humus of the soil. The total land layer is fed precisely from humus, therefore, the higher the nitrogen content in humus is, the more rich the soil is in nitrogen compounds. The decomposition of humus in contact with organisms in the soil proceeds slowly, ultimately, plants can receive no more than 1% of the nitrogen from the total amount contained in the humus.
Most nitrogen is contained in soil humus
The plant is able to absorb and assimilate nitrogen in the soil only at the end of the mineralization process, which is caused by microorganisms. As mentioned above, this process takes a lot of time, the amount of which varies depending on environmental factors, such as:
- Chemical properties of the soil itself.
- Humidity level
- The average temperature in the region.
- The degree of aeration.
The importance of nitrogen in plant activity
Nitrogen plays a fundamental role in the formation of the roots and the stem of a plant, therefore gardeners try to fertilize their crops with nitrogen compounds, especially diligently at the initial stage of development. Nitrogen fertilizers allow the plant to develop leaves and flowering much faster and in larger quantities than plants that do not fertilize with nitrogen.
Nitrogen plays a fundamental role in the formation of the roots and stem of a plant.
Most of the nitrogen goes into the educated young shoots and leaves of the plant. As it grows, the stored nitrogen moves through the stalks from the already grown leaves to the new ones.
Overfeeding with nitrogen causes a slightly different effect: the plant begins to accumulate a lot of roots, stem, leaves, but the ripening of flowering and fruit is strongly inhibited, for this reason it is necessary to strictly observe the dosage of fertilizers.
Lack of nitrogen also has a retarding effect on growth.
Lack of nitrogen also has a retarding effect on growth, but not only of the fruit, but of the whole plant organism as a whole. The stem and leaves of plants suffering from a lack of nitrogen, look weak and have a yellowish color. Lack of nitrogen causes a lack of chlorophyll, without a sufficient amount of which normal absorption of plant sunlight is impossible. Poor quality of photosynthesis and causes inhibited development, weakness of the plant, yellow color of leaves and stems.
Properly fertilized with nitrogen, the plant not only grows faster and produces more fruits, but the quality of the crop grows due to the increased protein content in them. Nitrogen is contained in all protein compounds, a competent increase in the dose of top dressing allows to enrich the crop with useful substances.
Expected large crop can be obtained only by feeding the plants in strictly limited dosage. Excess nitrogen fertilization, or lack of nitrogen nutrition, will inhibit the development of both individual crop representatives and low yields in general.
Fertilizer classification with nitrogen
Fertilizer classification by nitrogen form
The classification of nitrogen fertilizers contains 5 main groups, divided by the concentration of nitrogen and additional substances in the composition:
- Nitrate. Characterized by the content of calcium, sodium nitrate.
- Ammonium. Fertilizers with sulphate and ammonium chloride content.
- Ammoniac—nitrate. A complex group of fertilizers containing both ammonium and nitrates. One of the representatives of the class of the complex group is ammonium nitrate.
- Amide. The most common group fertilizer is urea.
- Ammonia. A group of fertilizers, liquid in composition. Examples: ammonia water, anhydrous ammonia.
The aggregate state of nitrogen fertilizers is of 2 types, liquid and solid. In gardening, mainly liquid form of fertilizers is used due to its efficiency and ease of use. The main constituent element of such fertilizers is ammonia.
The use of nitrogen fertilizers
Soil enrichment with nitrogen fertilizers increases the yield of the entire crop
Soil enrichment with nitrogen fertilizers helps to solve most problems with fertility and the growth of planted plants.
The main advantages of using nitrogen fertilizers:
- Acceleration of the growth of plant organs: stems, roots, foliage.
- Saturation of plant amino acids at a young age.
- Improving the water balance of the plant.
- Acceleration of mineralization processes of other soil fertilizers added after nitrogen.
- Improving plant resistance to the environment and damage.
- Increase the yield of the entire crop.
Nitrogen Fertilizer Production
Nitrogen cycle in nature
The process of obtaining nitrogen fertilizers takes place by mixing two types of gas: hydrogen and nitrogen. Burning coke inside the generator set abundantly releases nitrogen, which is mixed with hydrogen — the product of burning oil or coke.
Mixed gases form an ammonia compound, subsequently becoming the basis for future fertilizer. Also during the reaction, another product arises - nitrate acid, from which fertilizers-nitrates are produced.
Scope of application and dosage
Cultures after nitrogen fertilizers produce greater yields.
Almost all crops after nitrogen fertilizers produce greater yields. The only exceptions are legumes that do not need nitrogen for growth. The rest of the standard set of vegetables and berries for the garden: potatoes, cucumbers, tomatoes, carrots, strawberries, flowers, etc., give a significant increase in yield after using nitrogen fertilizer.
The generally accepted rate of application of fertilizer for different crops is as follows:
Nitrogen Fertilizer Features
Fertilizers in the form of ammonium sulfate and ammonium nitrate are more widely used. Nitrate compounds are used much less frequently, but at the same time they have their own advantages, do not acidify the soil mixture, which in some cases is very important for plants. To this group can be attributed sodium and potassium structure.
Amide fertilizers are the most well-known and common type of nitrogen fertilizer among gardeners and farmers. A special representative of this group is urea.
Nitrogen impurities are introduced into the earth mixture when planting plants and for their further feeding. And also they are brought in to enrich the land with mineral components during the plowing of the plot.
Nitrogen fertilizers are used for the care of fruit and vegetable plants, so for indoor cultures. First of all, nitrogen affects the development and increased density of green masses, and an excessive amount of nitrogen can lead to a delay in flowering of the crop. It is necessary to take into account the fact that cultures with bulbous, woody or branched roots most in need of nitrogen vision, which should be introduced into the soil from a very early age. In the initial period of growth, root crops do not fertilize at all; they begin such actions only after the development of strong foliage.
And also it must be remembered that because of its artificial origin, such components can bring some harm to plants, in the case of incorrect dosage and unsystematic introduction.
Despite the fact that nitrogen fertilizers can be of three typesThere are also several subspecies of their compounds.
Ammonium and ammonium dressings
Ammonium sulphate is a top-dressing that carries 21 percent of nitrogen in it, it just dissolves in water and almost does not clot. As well as the tool is a valuable supplier of sulfur, which is in such a compound in the amount of 24 percent. According to its composition, it refers to the salt of a neutral content, but when absorbed by plants it becomes an acidifying agent.
To apply fertilizer on acidic soils should be carefully and at a certain dosage or replace it with other drugs. And also with extreme caution should be used on brown, gray forest, sod-podzolic soils, yellow soils and red soil. In such areas, ammonium sulfate is used only in conjunction with alkaline phosphorus impurities, for example, with lime, phosphate rock and tosslag.
Acidification of the earth using ammonium sulfate should be avoided on semi-desert and chernozem soils, since they contain a large number of free carbonates that neutralize its effect.
Irrigation of the earth will become the best method of top dressing. The experience of many gardeners shows that ammonium sulfate is not very effective when applied to the soil.
Ammonium chloride is a crystalline component that contains 25 percent nitrogen. It is well soluble in water and slightly hygroscopic. Like ammonium sulfate, it gives the soil increased acidity, so you need to take into account the same contraindications to acidity and combine ammonium with alkaline fertilizers to neutralize the mixture.
It should be particularly careful and use ammonium chloride, only following the manufacturer's instructions, since the chlorine contained inside can be poorly tolerated by some crops in the garden, they can die from its introduction. Such plants with hypersensitivity include: grapes, potatoes, citrus fruits, flax, tobacco, buckwheat, fruit and vegetable or vegetables. Winter crops and grain crops equally affect fertilizers.
Calcium and sodium nitrate belong to this group of fertilizers. Such alkaline compounds react well with acidic soil can also be used together with other means that have an acidic reaction.
Sodium nitrate contains 16 percent nitrogen. Organoleptic features: crystalline powder, is hygroscopic and just soluble by water. Most often, this fertilizer is used for the cultivation of root crops, for which they are introduced into the soil during planting, and after that, the plant itself is watered directly with a solution with weak acidity.
Potassium nitrate carries 15 percent nitrogen. It dissolves rapidly in water and has a high hygroscopicity index, which is considered an indication for sale and storage in well-packed plastic bags. Такое удобрение лучше всего подойдёт для кислых по составу почв либо нейтрализации других составов, оказывающих особый эффект кислотности.
К этой группе можно отнести известково-аммиачную и аммиачную селитру.
The total amount of nitrogen in this fertilizer comes to 35 percent. Ammonium nitrate is hygroscopic, so it must be stored in well-packed bags, waterproof type. When entering into the soil saltpeter needs to be combined with freshly sour lime, the ratio is calculated from a ratio of 7: 3. This method is more often used with machine fertilizer fields. The production of nitrogen fertilizers occurs with the addition of a component that absorbs excess moisture and belongs to the disintegrators. Such a component may be phosphate flour., ground limestone and chalk.
Ammonium nitrate quickly dissolves in water, and therefore, when irrigated, it is not diluted with water, but introduced when planting crops in a dry format. You should not use this fertilizer yourself on soils with a high level of acidity, as this aggravates their HP reaction.
Ammonium nitrate can be used for planting and re-fertilizing plants. Most often it is used for the cultivation of beets, cereals, potatoes, tilled and winter crops.
Lime-ammonium nitrate contains up to 20 percent of nitrogen, and because of the presence of calcium carbonate in the composition is considered a more favorable plant for fertilizer.
The amide fertilizers include urea, which is second in nitrogen content. It contains 46 percent of it. Fertilizer is produced in the form of granules, covered with a protective film, which contains fats that do not allow the substance to clog. When using urea, it should not be distributed superficially to plants.
This is attributed to the fact that, reacting with soil bacteria, it changes to carbon dioxide ammonium. It is more simple and accessible for the absorption of cultures form. But it must be remembered that, interacting with open air, it begins to decompose actively, including ammonium gas ammonia, and the positive result of fertilizer application in the soil decreases as it evaporates.
- Urea is considered universal in its use and helps to increase fertility and yield of various plants in the garden several times. Especially it is recommended to apply it on soils that are regularly moistened, since it has less property of other substances to be washed out with water.
- Calcium cyanamide. Includes 20 percent of nitrogen in its composition, is insoluble in water, dark-colored powder, refers to alkaline feedings due to the large amount of calcium in the composition. Recommended for use on acidic soils, which are quickly neutralized by this composition. But it is necessary to limit its use or use it together with acid fertilizers on alkaline soil.
- This fertilizer is very important to make as early as possible before planting the plant, since when contacting with the soil and the bacteria in it, cyanamide is formed, which can weaken the crop or even provoke its death. But after some time, such a substance changes to urea. This will take at least ten days, so fertilizers are applied to the soil in advance, even before the sowing process. As well as fertilizers are used as an additional top dressing, which is applied in early spring or in the fall in the soil itself.
Liquid ammonia is in first place by the amount of nitrogen - 82.3 percent. The process of creating it is quite difficult, the substance can be obtained by burning ammonia gas. Anhydrous ammonia should not be stored in an open place, since it is inherent to evaporate, and it also leads to corrosion of metals: copper and zinc, but does not affect iron, steel and cast iron, because of this it is customary to store dressing in thick-walled tanks made from these metals.
- Ammonia liquid is a top dressing, which is a solution of ammonia in water, where such nitrogen is present in an amount of 15-20 percent. Storing the mixture does not entail any special costs. Ammonia water does not interact with ferrous metals, and it can be stored in simple vessels made of carbon steel.
- Such nitrogen mixtures are introduced into the soil itself to a depth of 10 centimeters in the spring before the start of sowing or in the fall, when the harvest of fruits was already cleaned and plowing began, for this purpose special machines are used. Most often, nitrogen mixtures are used to feed perishing plants.
- Industrial ammonia is obtained by dissolving more solid forms, such as urea and nitrate. The nitrogen content in such solutions reaches 50 percent. For their storage using special sealed tanks created from aluminum or containers made of polymers. Ammonia act on the soil and plant in the same way as solid nitrogen fertilizers.
Nitrogen blend application
Nitrogen-type fertilizers quickly and easily dissolve in water, therefore they reach the plant root system in a short time.. More effective method their use will be introduced into the ground directly under the roots of the culture in the springtime, when the lack of such a component has a very strong effect on the developing plant.
The decision on which nitrogen fertilizers to use should be justified and carefully weighed in each case. It is not recommended to bring them into the soil in autumn, this restriction applies to shrubs and perennial trees, as this can reduce their resistance to frost and in the event of severe cold, the culture often dies.
What is nitrogen fertilizer and how to apply them correctly
The effect of nitrogen fertilizers on plants is difficult to overestimate or overlook. It immediately catches the eye in the form of dark green lush foliage. The application of nitrogen fertilizers in spring is a guarantee of proper growth of garden crops, flowers, bushes and trees.
Nitrogen is involved in the formation of protein molecules and is an important element in the composition of chlorophyll, without which the process of photosynthesis is impossible. Among the signs of nitrogen starvation are yellowing of foliage, lag of plants in growth, premature flowering.
Some nitrogen contains manure and bird droppings, especially pigeon, chicken and duck. Organic fertilizers containing nitrogen can be obtained by composting plant waste. On average, compost from plants such as lupine and clover contains 0.4-0.7% nitrogen, from green foliage - about 1%. Most nitrogen plants can get from lake sludge - 2% or more.
Usually, plants need additional fertilizing with nitrogen fertilizers, since the nitrogen in the soil becomes available for their roots only after mineralization by the microorganisms living in the earth. With proper feeding, the plants develop faster, form large dark green foliage, and accumulate protein in the fruit.
But overdoing with nitrogen fertilizers is still not worth it, it adversely affects the ripening of fruits, because the plants send all their strength to the formation of green mass. In addition, an overdose of nitrogen in the soil worsens the survival of plants during transplantation, inhibits the ripening of wood.
Nitrogen content in the soil
It is established that a significant proportion of nitrogen in the earth is concentrated in its layer, called humus, in it more than 5% nitrogen. Naturally, the thicker the humus layer, the greater the amount of nitrogen, therefore, the plants feel better on this soil.
Humus is a very resistant substance, the process of its decomposition is slow, therefore, the release of mineral substances from this layer also occurs rather slowly. Only one percent of the five that are in the soil is a mineral compound, soluble in water, and, therefore, available for consumption by plants.
Consequently, even in the presence of a thick layer of humus, additional fertilizing plants are necessary, albeit at lower doses.
Why do plants need nitrogen?
This element, it turns out, is not in every organic compound. For example, there is no nitrogen in sugars, fiber, butter and starch. There is nitrogen in the amino acid and protein. Nitrogen is an important component of nucleic acid, which is the main component of literally any cell responsible for protein synthesis and duplication of hereditary data (duplication is the formation of additional hereditary material identical to that already in the genome).
Even chlorophyll, which, as you know, promotes the absorption of solar energy by plants, also has nitrogen in its composition. In addition, nitrogen is present in various components of the organic medium, for example, in alkaloids, lipids, and similar substances.
The entire above-ground mass of plants has nitrogen, and most of this element is contained in the very first leaf plates. With the completion of flowering and the beginning of the formation of the ovary, this substance flows to the reproductive organs of plants and accumulates there, forming proteins.
During seed ripening, nitrogen is taken from the vegetative organs in the maximum amount, and they are greatly depleted. If there is a lot of nitrogen in the soil and the plant consumes it in large quantities, then this element will be distributed to almost all plant organs, which will lead to rapid growth of the above-ground mass, delays in the ripening of berries and fruits and a decrease in the total yield of plants.
Only a balanced concentration of nitrogen in the soil can be a guarantee of high yields and sufficient product quality.
Those plants that consume nitrogen in abundance, and not in excess, can fully develop, form standard leaf blades of a typical, often green, color, otherwise they will wither and form mediocre yields.
Corn, treated with nitrogen fertilizers (background) and not processed
Nitrogen-containing fertilizer types
Nitrogen fertilizers - These are substances that contain nitrogen compounds. In total there are several major groups of nitrogen fertilizers. These are nitrate fertilizers (calcium and sodium nitrate), ammonium fertilizers (ammonium chloride and ammonium sulfate), ammonium nitrate fertilizers (ammonium nitrate), amide fertilizers (urea), and liquid nitrogenous fertilizers (ammonia water or anhydrous ammoniac).
Nitrogen fertilizers, nitrate group
Let's start with calcium nitrateIs its chemical formula Ca (NO₃) ₂. Externally, calcium nitrate is a white granules, in which nitrogen contains up to 18%. This fertilizer is suitable for soils with high acidity. With the planned and annual introduction of calcium nitrate into the soil with high acidity, improvement of its properties is observed. Calcium nitrate is perfectly soluble in water, so you need to store fertilizer in bags that do not let water through.
When making calcium nitrate it must be remembered that its mixing with phosphate fertilizers is unacceptable.
The next fertilizer is sodium nitrateIts chemical formula is NaNO₃. This fertilizer is crystalline, it contains slightly less - up to 17% nitrogen. Sodium nitrate is highly soluble in water and is well absorbed by the roots of plants. This fertilizer is universal and suitable for different crops. This fertilizer can not be applied in the autumn period: the nitrogen contained in it will be actively washed into the groundwater.
Given the excellent solubility in water and hygroscopicity, this fertilizer should be stored in dry places.
The next group is ammonium fertilizers. In the first place in this group is ammonium sulfateits chemical formula is (NH4)2SO4 . Externally, this fertilizer is a white powder, which contains a little more than 20% nitrogen.
Ammonium sulfate can be used both as the main nitrogenous fertilizer and as an additional top dressing. The application of this fertilizer can be carried out in the autumn period: nitrogen from it is fixed in the soil, without being washed into the ground water.
With the annual and systematic introduction of ammonium sulfate into the soil, soil acidification may occur, for which this fertilizer must be mixed with lime or chalk in a ratio of one to two.
Ammonium sulfate is not hygroscopic, so there is usually no problem with storing its problems. The main thing to remember is that it is impossible to apply this fertilizer in combination with any alkaline feedings, because there is a risk of suppressing nitrogen activity.
Ammonium chloride, Is its chemical formula NH₄Cl. This fertilizer contains about 26% nitrogen. Externally, ammonium chloride is a yellow-white powder. When applying ammonium chloride is not observed leaching it from the soil, during storage, this fertilizer does not clot, and even after many years of storage does not require grinding. Nitrogen released from ammonium chloride into the soil, well absorbed by plants.
The main disadvantage of this fertilizer is chlorine contained in its composition. So, when entering into the soil 10 kg of nitrogen, in terms of the active substance, about twice as much chlorine enters the soil, and it is considered poisonous for most plants. Considering this, the introduction of ammonium chloride should be carried out exclusively in the autumn period in order to deactivate the chlorine component, but at the same time up to 2% of nitrogen is lost.
Ammonium nitrate fertilizer
The next category is ammonium nitrate fertilizers, the leader in this group is ammonium nitrate. Chemical formula ammonium nitrate looks like this - NH₄NO₃. This fertilizer has the appearance of a whitish granular powder. Fertilizer contains about 36% nitrogen. Ammonium nitrate can be used as a basic fertilizer or as an additional fertilizer.
This fertilizer is categorized as a non-ballistic substance, so its main use falls to regions with a deficit of water moisture. It is noteworthy that on soils with an excess of moisture, the effectiveness of the use of this fertilizer is reduced to a minimum, since the nitrogen contained in the fertilizer is almost completely washed into the groundwater.
Ammonium nitrate due to increased hygroscopicity does not tolerate storage in damp areas, where it quickly hardens and compresses. Of course, this does not mean that the fertilizer becomes useless, just before it is applied to the soil, it will be necessary to grind the saltpeter, which is sometimes quite difficult.
If your plan is to create a mixture of ammonium nitrate and phosphate fertilizer, for example, superphosphate, then you should initially mix superphosphate with any neutralizing fertilizer, for example, dolomite flour, chalk or lime and the next step - mix it with ammonium nitrate.
Do not forget that the planned and annual introduction of ammonium nitrate into the soil leads to an increase in its acidity level. It is noteworthy that the level of acidity of the soil increases most actively with time, and in the initial stages of its introduction, the change in acidity is imperceptible.
In order to prevent soil acidification, ammonium nitrate must be applied along with chalk, dolomite flour and lime in a 1: 2 ratio.
Interestingly, at present, ammonium nitrate in its pure form is practically not implemented, sell it in the form of various kinds of mixtures. The mixture consisting of 60% of ammonium nitrate and 40% of various neutralizing components enjoys great popularity and has good reviews. In this ratio in the mixture is about 19-21% nitrogen.
Nitrogen Fertilizer Granules - Urea
Group - amide fertilizers
Urea- its chemical formula is CH4N2O Urea is called otherwise - carbamide, this fertilizer is considered one of the most effective. Urea contains about 47% nitrogen, sometimes - 1% less. Externally, it is white granules. This fertilizer is characterized by an increased ability to acidify the soil, therefore it can be applied only with neutralizing substances - dolomite flour, chalk, lime. Urea is very rarely used as the main fertilizer, it is usually used as an additional foliar dressing. This excellent foliar fertilizer is also because it does not burn leaf blades, but is well absorbed by plants.
There are two known brands of urea, which are called - A and B. Mark under the name A does not belong to the category of highly effective and is rarely used in crop production. Usually, grade A urea is used as a feed additive for animals, for example, goats, cows, horses. Brand name urea with the name B - is treated with additives urea, used precisely as a fertilizer.
Liquid nitrogen fertilizers
Ammonia hydrateor ammonium hydroxide (ammonia water or liquid ammonia). Chemical formula of ammonium hydroxide NH4OH. In essence, ammonia water is ammonia dissolved in water. In total there are two types of liquid ammonia, the first one contains nitrogen not less than 19% and not more than 26%, and the second one can contain from 15% nitrogen to 21%. Usually ammonia water is applied with special equipment capable of embedding this fertilizer into the soil to a depth of about 14-16 cm.
The advantages of liquid fertilizers are their extremely low price, fast digestibility by plants, the long period of action and the uniform distribution of fertilizers in the soil. Есть и недостатки, – это довольно сложная транспортировка и хранение, возможность образования сильных ожогов на листьях при попадании удобрения на их поверхность и необходимость в специальной технике, предназначенной для внесения жидких удобрений.
Органические азотные удобрения
Как известно, азот присутствует в органических соединениях, однако его количество там невелико. Так, например, в помете крупного рогатого скота азота не более 2,6%. In bird droppings, which are quite toxic, it is up to 2.7%. Nitrogen is also present in the compost, but its amount there, depending on the “ingredients” of the compost, is very different. Most of the nitrogen in the compost is prepared from lake sludge, leaf litter, green mass of weeds and lowland peat. Given the instability of the nitrogen content in organic fertilizers, its use as the main fertilizer is not desirable and threatens nutritional deficiencies and nitrogen starvation for plants. On top of that, such fertilizers, though slowly, still acidify the soil.
Organic nitrogen fertilizer
Cultures for which nitrogen is especially important
In general, every crop needs nitrogen, but the dosage for each crop varies. Given this, all plants can be grouped into categories of the need for nitrogen.
In the first category You can include plants that need to be fed with nitrogen before planting them in the ground to activate growth and development. For such crops per square meter you need about 26-28 grams of nitrogen in terms of ammonium nitrate and per square meter of area. This category includes, from vegetable crops: potatoes, cabbage, bell peppers, eggplants, zucchini, pumpkin and rhubarb, from berries and fruits: plum, cherry, raspberry, blackberry and strawberries, from flower: lilac, rose, dahlia, peony, violet, phlox, balsam, cloves, nasturtium and zinnia.
Second group - These are cultures that need less nitrogen. Usually, only 18-19 g of nitrogen in terms of ammonium nitrate and per square meter of area are sufficient. From vegetable crops you can include: tomatoes, parsley, cucumber, carrots, corn, beets and garlic, from fruit and berry: apple, currant, gooseberry, from flower: all annuals and delphiniums.
Third category - These are plants that need nitrogen in moderate quantities, not more than 10-12 g per square meter in terms of ammonium nitrate. Vegetables in this category can include: early ripening potatoes, lettuce crops, radishes and onions, from fruit - is a pear, from flowers: bulbous, primroses, adonis, saxifrage and daisy.
Final category requires the introduction of a minimum amount of nitrogen per square meter, not more than 5-6 g in terms of ammonium nitrate. From vegetable crops, it is possible to include spicy herbs and legumes, from flower plants - poppy, azalea, young, heather, stonecrop, Erica, purslane, rhododendron and cosmea.
Nitrogen Fertilizer Rules
Remember that only optimal doses of nitrogen fertilizers can positively affect the development and growth of various crops, and fertilizing needs to be able to calculate, based on the percentage of nitrogen in a particular fertilizer, and also to make them according to the type of soil, season and type of plant.
For example, when nitrogen is introduced into the soil in the fall, there is a risk that it will be washed into the groundwater. Therefore, the most suitable period for the application of fertilizers containing nitrogen is spring.
If you plan to fertilize soils with high acidity, then be sure to mix nitrogen with various neutralizing acidifying effect components - chalk, lime, dolomite flour. In this way, fertilizers will be assimilated better, and the soil will not acidify.
Residents of the steppe zone and forest-steppe, where the soil is predominantly dry, it is very important to apply nitrogen fertilizers periodically, without abrupt interruptions that can affect plants in the form of delays in growth, development, and decrease in yield.
It is better to carry out the application of nitrogen fertilizers to the black earth soil 11-12 days later after the snow melted. It is desirable to carry out the first top-dressing using urea, and when plants enter the active phase of the growing season, it is recommended to add ammonium nitrate.
Can there be harm from nitrogen fertilizers?
Yes, maybe in case of their oversupply. Usually, with an excess of nitrogen, the above-ground mass of plants begins to develop too actively, the shoots thicken, the leaf blades increase, the internodes become larger. The green mass acquires atypical pomp and softness, and flowering is either weak and short, or does not occur at all, therefore, the ovary is not formed and fruits and berries are not formed.
If there is a lot of nitrogen, then something like burns appears on the leaf blades, then these leaves die off and fall prematurely. The death of foliage sometimes leads to partial death of the root system, which is why nitrogen introduction must be strictly normalized.
Results So, we understood that all plants need nitrogenous fertilizers, however it is necessary to correctly determine their dosages and apply them in accordance with the recommended terms, relying, among other things, on the properties of the fertilizers themselves.