Nitrogen fertilizers for tomatoes: how to apply them correctly for a high-quality harvest

Nitrogen fertilizers for tomatoes support plants in the initial stages of development, at the stage of gaining green mass and the formation of strong stems, large leaves and fruit clusters. Nitrogen is contained in organic substances, mineral preparations and a relatively recent discovery by scientists - organomineral compounds. Like all fertilizers, fertilizers with nitrogen will be beneficial if used correctly.

Why do tomatoes need nitrogen?

The mineral is one of the most necessary elements for the harmonious development of tomatoes throughout almost the entire growth period. With a sufficient amount of nitrogen, the crop grows shoots and leaves and forms generative brushes. Healthy, well-developed and abundantly fruiting beds with tomatoes are possible only if there is a sufficient nitrogen component in the soil, which is constantly replenished by applying fertilizers. Nitrogen, which is present in the air, is processed by microorganisms into a form that can be absorbed by plants, in very small quantities. Gardeners who hope to get a good harvest of tomatoes enrich the soil with nitrogen fertilizers.

The plant needs the element before the fruits ripen, selecting it from the entire green mass and accumulating it in the seeds. Therefore, after fruiting, the bushes wither. At the same time, an excess of the element in products can harm human health. Thus, nitrogen fertilizing is stopped when the fruit begins to fill.

How to keep seedlings healthy

The first nitrogen fertilizing for tomatoes is carried out a week after transplanting the seedlings into open beds. After treatment, the bushes will actively grow and begin to increase green mass.

The second treatment is carried out at the moment of formation of the ovaries in order to prolong the stage and increase the yield. It is important not to overdo it with the amount of nitrogen, otherwise the tomato bushes will be lush and green, but there will be fewer ovaries and fruits or there will be no fruits at all.

The treatment is carried out not only in the open ground, but also in the greenhouse. When applying complex compounds with phosphorus, you need to wait until the soil warms up to +15 °C, otherwise the plants will not absorb the substance, and it will accumulate in excess in the soil.

Considering that nitrogen fertilizers for tomatoes in a greenhouse also contain other useful elements, you need to clearly understand when and how much to use them. Seedlings, in addition to nitrogen, need potassium - it stimulates the formation of fruits. Potassium in the fertilizer must be in sufficient quantity to ensure development and increase resistance to diseases and temperature changes. In addition to the listed elements, tomatoes need boron, magnesium, copper and manganese.

Signs of nitrogen deficiency

The main symptom of a poor amount of nitrogen in the soil is a change in the rich green color of tomato leaves. When an element is missing:

• stems and leaves become yellowish or pale green;
• leaf blades become smaller;
• thin stems stretch;
• the leaves at the bottom of the stems turn yellow and may fall off;
• During the day, the tops of the tomatoes curl.

Only a combination of signs can be a signal for applying nitrogen fertilizers to tomatoes. If the soil was enriched in the fall and spring, fertilizers were applied, and regular watering was carried out, some symptoms indicate the development of diseases.

Fertilizing methods

There are 2 ways to apply nitrogen fertilizers:

• root;
• foliar.

The root method involves watering tomatoes with nutrient solutions. This method is very popular because it is very simple and effective. Most gardeners fertilize tomatoes in their plots this way.

The foliar method of adding nutrients is to spray the leaves and stems with prepared solutions. This method is less popular, however, it is also very effective. The plant absorbs nutrients much faster from the leaves. When watering tomatoes at the roots, only some of the minerals will be absorbed by the root system. In this case, nutrients will be quickly washed away by rain.

Important! When foliar feeding tomatoes, the nutrient solution should be much weaker than for watering.

A solution that is too concentrated can burn the leaves. Under no circumstances should substances containing chlorine be used for spraying. The best time for foliar feeding is morning or evening. In the scorching sun, even a weak solution can cause burns. Of course, it is necessary to carry out both root and foliar feeding. Experienced gardeners alternate them, using the most suitable fertilizers.

Types of nitrogen fertilizers

Now the industry produces a large number of ready-made nitrogenous fertilizers for tomatoes only on a mineral basis or with the inclusion of organic matter. In many household plots, fertilizing is carried out traditionally - mainly with organic matter, which remains after farming and household management.

Mineral springs

Nitrogen fertilizers are produced in several different forms:

• a large amount of nitrogen in ammonium sulfate compounds and other preparations with ammonium;
• the most popular remedy in household plots is urea or urea, in which nitrogen is in amide form;
• nitrate form of nitrogen in nitrate - sodium and calcium, most often used on acidic soddy-podzolic soils;
• Another popular fertilizer, ammonium nitrate, contains nitrogen in nitrate and ammonium forms.

The amount of nitrogen component of any drug is determined by looking at its formula, which is usually shown on the package as a percentage. The following fertilizers are most often used on private farms:

• nitroammophoska is a complex preparation with a balanced composition of nitrogen, phosphorus and potassium;
• superphosphate with a small proportion of nitrogen, which does not increase the acidity of the soil;
• ammonium nitrate contains up to 35-40% nitrogen, and is often used with urea, but agricultural technology requires strict adherence to the recommended dose of this fertilizer;
• carbamide (urea) with 46% element content is applied to any type of soil only in the form of a solution, from which the nitrogen part is easily absorbed by tomatoes and remains in the soil for a long time;
• ammonium sulfate with almost equal contents of nitrogen and sulfur, 20% and 24%, respectively, is used at the initial stages of tomato growth as an easily soluble and digestible preparation;
• calcium nitrate, a product with a short shelf life, contains only 15% nitrogen, has little effect on the acid composition of the soil, like other similar substances, so the fertilizer is more often used in the non-chernozem zone.

Attention! Urea is a fertilizer with a high proportion of nitrogen component, easily dissolves and is well absorbed by plants, effectively increasing the yield of tomatoes.

Organic sources

Preferring the principles of organic farming, many gardeners add traditional fertilizers to the soil based on the waste of domestic animals or plant residues.

Compost

Organic material is often created from peat. For compost, crushed plant remains and various food waste are collected and compacted. The mass should burn out within a year, and when it becomes homogeneous, it is applied as fertilizer for tomatoes.

Humus

After rotting for a year, manure from domestic animals is widely used in agriculture: cow, horse, goat, sheep, rabbit or pig. In the summer, use a solution of fresh mullein, diluted in a ratio of 1:5, a useful nitrogen fertilizer.

Bird droppings

The substance is very active, in fresh and dry form in high concentrations it can burn the roots of tomatoes. When used in solution, the litter is diluted in a ratio of 1:15. Often the substance is added for composting.

Herbal infusion

Green weeds or any meadow grass are used as an effective and harmless nitrogen fertilizer for tomatoes. The use of nettle, plantain, and dandelions is especially useful. The green mass is poured with two parts of water, bread with sugar or yeast is added for fermentation and left in a closed container for a week. When watering the tomatoes, add 1 liter of infusion to a bucket of water. A simple nitrogen product is valued due to its high content of substances necessary for tomatoes in a form that is easily absorbed by plants.

Warning! Wood ash is a source of potassium, calcium and phosphorus; it is not digested along with mullein and chicken droppings. These types of organics are not used together.

Organomineral fertilizers

A relatively recent development by manufacturers is organomineral fertilizers (OMF), complex products based on organics and minerals. Ready-to-use drugs are produced in the form of liquid concentrates, granules or powders:

• potassium and sodium humates, after the use of which nitrates do not accumulate in fruits, are produced on the basis of manure and peat, the required amount of mineral elements and active microorganisms for fertilizing tomatoes at all stages of development;
• “Baby” is a balanced fertilizer made from peat, dolomite flour, nitrogen, potassium and phosphorus, used for tomato seedlings, increasing plant immunity, and has a beneficial effect on the formation of a developed root system;
• “Signor Tomato”, created on the basis of an organic extract and a complex of useful microelements, promotes abundant fruiting and improves the taste of the crop;
• In addition to organic matter, the OMU “Universal” preparation includes substances that help protect plants from fungal diseases; its composition is safe for humans and does not cause allergies.

Important! The popular nitrogen fertilizer “OMU for tomatoes” is used when planting plants, and the bushes are also fed by directly adding granules to the soil with a dosage of 30 g per 1 square meter. m.

Mineral nutrition

The following mineral fertilizers have been very popular for decades:

• Urea (urea) is a highly effective granular nitrogen fertilizer that increases the yield of tomatoes and their resistance to diseases and pests. It is highly soluble in water; it is added during watering of plants (20-30 g per 10 liters of water). It can be applied to the soil and in dry form (sprinkle 3-4 g onto the garden bed and mix with the soil), and can also be used for spraying plants (50 g per 10 liters of water).
• Saltpeter occupies one of the leading positions in the ranking of popular mineral fertilizers. This fertilizer comes in different types: ammonia, calcium, potassium, sodium, magnesium - it all depends on the soil on which the crop is grown. To feed tomatoes, experienced vegetable growers most often use ammonium and calcium nitrate.
  Calcium nitrate is necessary for the active growth of tomatoes, strengthening their root system and immunity. Ammonia is useful for ensuring a high yield of vegetables. To ensure that this fertilizer does not cause harm to plants, it is necessary to carefully monitor the dosage of the drug and the feeding schedule.

  Each package of this mineral fertilizer has instructions, but most often for root feeding, 25 g of nitrate is diluted in 15 liters of water.

• Superphosphate is a complex mineral fertilizer containing nitrogen-phosphorus compounds. The drug is applied directly when digging into the soil in spring or autumn, or directly into the hole when planting seedlings (1 tsp per plant). Used on any soil, it is easily absorbed by tomatoes, making them more juicy and tasty.

Timing for applying fertilizers with nitrogen

When growing tomatoes, fertilizing with nitrogen fertilizers is carried out regularly during the first 3 months of crop development, before fruiting begins.

Feeding seedlings

While growing in cups, tomato seedlings develop 10-12 complex leaves and begin to form flower clusters. For successful growing season, plants need a full set of nutrients. Most of all, at this stage, tomatoes need nitrogen to gain green mass.

The first time tomato seedlings are given nitrogen fertilizer is when two true leaves begin to form, a week before picking. Dilute 1 tablespoon of urea in 10 liters of water and water the seedlings.

The next feeding is 7-10 days after picking. At this time, tomatoes require, in addition to the necessary nitrogen, phosphorus and potassium, increased immunity and development of the root system for better survival. Dilute 1 tablespoon of nitrophoska or azofoska in a liter of water. Gently water the plants with the solution so that the fertilizer only reaches the soil. After these first fertilizing, which due to the presence of the nitrogen component increases the acidity of the substrate, it is necessary to add compost or vermicompost to the pot after 2-3 days.

The last, third feeding is carried out with the same composition as the second, 10-15 days before planting in a permanent place. When adding fertilizer to seedlings, pay attention to the appearance of the sprouts and the conditions in which they are grown. In addition to nutrition, it is also important for the crop to comply with the requirements for lighting, comfortable temperature and moderate watering.

When transplanting seedlings into the ground

Nitrogen fertilizers for tomatoes are very necessary during the period of plant development after planting in a permanent place. A rich and high-quality harvest is possible if the tomato bush receives timely and balanced nutrition with nutrients:

• a little nitrogen and potassium fertilizer is added to the holes for planting tomatoes - 100 g of humus or compost and 30 g of wood ash;
• 7 days after planting, the tomatoes are fed with green infusion, to which mullein or ash is added;
• 15-18 days after planting, a complex of mineral preparations is used, which includes nitrogen, potassium and phosphorus agents;
• in the flowering phase, fertilizing is carried out, which promotes the formation of ovaries, using WMD, ready-made mineral complexes, mullein or bird droppings;
• At the beginning of fruit formation, tomatoes are sprayed with a mixture of wood ash and boric acid.

After fruit formation

Fertilizer with nitrogen for tomatoes is no longer used during fruiting. Otherwise, the bush will produce new shoots and leaves to the detriment of fruit formation. Only at the initial stage of ovary growth are they fed with superphosphate and sodium humate in a ratio of 2:1 per bucket of water. Continue to use mullein infusion, diluting it with water in a ratio of 1:6. A small amount of nitrogen fertilizer will be beneficial in creating strong fruit clusters. The following feeding of tomatoes is carried out only with superphosphate and potassium. During this period, various tomato ripening stimulants are used, which help increase the volume of fruits and improve their taste, such as “Solution”, “Ripener” and others.

Signs of improper feeding of tomatoes

You can overdo it with the dosage of fertilizers not only when using mineral mixtures. Organic substances in large quantities can also negatively affect tomato seedlings. The condition of the plant immediately shows that it is overfed. For example, a large amount of nitrogen will be visible in a large, spreading bush. Such a plant devotes all its energy to the formation of stems and leaves, so there is no energy left for the ovaries and fruits. And since we want to grow good tomatoes, and not a beautiful bush, we should use nitrogen fertilizers carefully.

Plants simply need nitrogen until flowers appear. Then fertilizing tomatoes with nitrogen should be stopped. In the future, plants will need nitrogen-containing mixtures only after the first fruits appear on the first cluster.

Nitrogen deficiency can be manifested by changes in leaf color. They will turn light green or even yellowish. Then they can gradually curl, and the old leaves will begin to die off. The surface of the sheet will become matte. The situation must be corrected immediately after the first signs appear. Organic lovers can feed tomatoes with herbal infusion. And as a mineral fertilizer you can use urea or ammonium nitrate.

Phosphorus is often present in nitrogen fertilizers. This substance helps tomatoes develop resistance to cold. A lack of phosphorus immediately affects the appearance of the leaves. They turn purple. Remember that tomatoes do not grow well in oily soils.

Important! Also, the cause of poor development of tomatoes may be an excess of minerals in the soil.

Urea is a very useful fertilizer for tomatoes. Many gardeners successfully use this substance. However, it should be remembered that urea can only be applied in the form of a solution. The soil is sprayed or watered with it. Under no circumstances should this fertilizer be applied in granular form directly into the hole.

Organic substances have always been considered safer and healthier for plants. But still, their number should not be excessive either. For example, you can use mullein to feed tomatoes no more than 3 times per season.

Excess nitrogen fertilizers

Receiving a lot of nutrition for growth, tomatoes form tops instead of flowers. Fruiting occurs late, and the ovary is not very abundant. If there is an excess of nitrogen in the soil, the tomatoes are said to be fattening:

• the stems grow too much, the bush becomes dense and spreading;
• many stepsons are formed;
• tomato leaves grow large, if this is not a varietal characteristic;
• ovaries are rarely formed.

With such obvious signs of an overdose of fertilizers on tomatoes, the effect of excess nitrogen is neutralized by adding a superphosphate solution. If nitrogen is in the soil in forms that are slowly absorbed, it can be overabundant in the fruits themselves, which negatively affects the health of consumers of the product. The presence of excess nitrogen compounds in tomatoes is determined only in laboratories after analysis.

Basic information

Fertilizer for seedlings should contain a whole complex of microelements useful for the active growth of green shoots: potassium, nitrogen and phosphorus. Typically, most commercial fertilizers contain equal amounts of the listed components. The importance of feeding young bushes with one of the listed elements should not be denied. For example, influence seedlings using nitrogen fertilizer.

The first thing gardeners should remember is that a considerable amount of nitrogen, important for plant development, is contained in the soil. This statement directly depends on the territorial location and climatic conditions of the area. The largest amount of the substance is observed in chernozem, and the smallest amount is found in sandstones.

About 5% of nitrogen is contained in soil humus, so the higher the content of this component, the better for gardeners. Humus itself is unusually stable. Its breakdown into mineral salts is extremely slow, so there is no more than 1% of nitrogen available for use by plants in the soil. However, this element is considered one of the most important for the active growth and development of all garden crops. The higher its content in the soil, the better the harvest.

The maximum need of plants for nitrogen occurs in the spring, when the planted seedlings begin to actively grow and develop in new growing conditions. To enrich the soil and saturate crops with useful microelements, special industrial fertilizer is used. Those who cannot afford it can prepare a similar composition with their own hands.

Mineral or organic: which fertilizers are better?

Depending on the type of feed used, their effect on the crops being treated may vary slightly. The most common are mineral and organic nitrogen fertilizers.

Mineral fertilizers contain a sufficient amount of nitrogen for the development of excellent seedlings, as well as their active fruiting. It is best to use non-sulfate options.

The most popular are such mineral fertilizers.

1. Urea is an ideal option as a primary effect. To prepare the solution you will need a bucket of water and a tablespoon of the active ingredient.
2. Superphosphate - used during the period when stronger leaves appear on the stems. To prepare, you will need a spoonful of fertilizer and a liter of water.
3. Saltpeter - to moisten the soil under the seedlings, a solution of a spoon of dry preparation and a bucket of water is used.
4. Ammonium - used in liquid form for watering seedlings (10 liters of liquid, 20 g of fertilizer).

Any organic fertilizing is permissible only at the early stage of growth of garden crops. The most effective of them:

• bird droppings - used as liquid fertilizer for watering the roots (1 kg of organic matter per bucket of water / leave for 4 days before use);
• mullein - cow dung soaked in water for a day is suitable for preparing fertilizer.

How to fertilize plants?

Many gardeners prefer to fertilize edible crops with organic fertilizers, mistakenly believing that natural substances will not cause harm. Everything requires moderation and the right approach: fresh manure can “burn” the roots, and ash added to the soil for seed germination delays the emergence of seedlings.

How to use what nature provides?

• Manure can be used only when it has been lying for at least a year; it is better to apply it as part of compost.
• Bird droppings should be mixed with double the amount of peat or straw. For liquid feeding, 10 g of litter should be mixed in a bucket of water.
• Compost is an excellent fertilizer made from rotted plants. When creating a compost heap, layer the grass with manure. To ensure that the mass is processed well, water it with biological products.
• Herbal infusion. It is best to use nettle; fill it with water and leave for 2 weeks in a closed container.
• Ash. Use only when plastic, film and other chemical compounds have not been exposed to fire. Apply ash separately from manure and compost; they reduce each other's effectiveness.

Manufacturers are also trying to prepare formulations that will feed the plants, but will not allow harmful substances to be deposited in the fruits. To feed tomato seedlings, you can purchase a complex fertilizer for a specific crop. It is more convenient to use drugs in liquid form, then you will be sure that there are no solid, undissolved particles left in the composition.

If you need nitrogen specifically, you can purchase the following substances:

• calcium or sodium nitrate containing 17% of this element;
• urea – 45%;
• ammonium nitrate – 45%.

Since tomato seedlings need not only nitrogen, it is better to use a complex fertilizer for feeding. All gardeners know nitroammofoska and azofoska; every year manufacturers produce more advanced preparations adapted for specific plants. To avoid making mixtures yourself, look for means for tomato seedlings. When purchasing, pay attention to the instructions: a conscientious manufacturer will definitely indicate what doses are needed for seedlings and what doses are needed for adult plants.

How do you know if feeding is needed?

There are many recommendations and schedules for fertilizing tomato seedlings, but every owner must learn to understand when his pets lack nutrition. The soil can be both fertile and poor; it may contain an excess of some components and a deficiency of others. It is best to use special soil for tomato seedlings; the manufacturer has already added the necessary substances to it and has written instructions indicating when to feed the plants. If you are preparing the soil for seedlings yourself, add all the necessary components to it: until the real leaves appear, the seedlings will feed only on what was originally put in the cups.

Healthy tomato seedlings have good strong stems and dark green leaves. If the greenery is too thick, you have overdone it with nitrogen fertilizers; from their excess, leaves and stepsons develop rapidly, and you may not have enough strength for flower trusses. When there are too many nitrates in the soil, tomato leaves cannot stand it, curl, and break easily. Excess fertilizer will also go into the fruit; instead of being beneficial, a salad made from such tomatoes can be harmful to health.

If the lower leaves of tomatoes turn yellow and fall off, the plant is low on nitrogen and needs feeding. Do not rush to immediately grab a bag of fertilizers if you notice that the seedlings are becoming lethargic and growing poorly. The reason may be incorrect temperature conditions, drafts, excessive watering, and disease. Make sure your tomatoes get enough light. Seedlings need good lighting, but it is also impossible to keep them under the lamps on around the clock: many biological processes take place only in the dark. If the living conditions of your pets are quite suitable, but they feel unwell, feeding is necessary.

Clear benefit or irreparable harm

According to some gardeners, most nitrogen fertilizers are extremely undesirable for constant use, as they have a rather negative effect on the health of crops. The reason is the ability of replenishment to accumulate in ripened fruits in the form of nitrates. This statement is partly true, but only if the dosage of substances added to the soil is incorrect.

It turns out that seedlings can indeed be harmed with the help of saltpeter or bird droppings, but only if an excessive amount of fertilizer is used. It is its excess amount that will settle in the ripened fruits of potatoes, leafy vegetables and beets.

If you follow the dosage and timing of application of the composition, you should not be afraid of the negative effects of nitrogen.

Phosphorus fertilizers for seedlings

Phosphorus not only participates in the synthesis of carbohydrates, but is also responsible for the normal development of the root system of seedlings. If you notice that the leaves and stems of plants have begun to darken and acquire a purple-purple color, then most likely they are experiencing a lack of phosphorus. The following phosphorus fertilizers will help replenish the reserves of this substance:

• potassium metaphosphate – 55-60%;
• double superphosphate – 50%;
• ammophos – 50%;
• diammophos – 50%;
• bone meal – 15-35%;
• phosphate rock – 20%;
• simple superphosphate - 15-20%.

To enhance the effect of fertilizing, phosphate rock or bone meal should be crushed as much as possible and mixed with acidic fertilizer or manure.

Potash fertilizers for feeding seedlings

Potassium helps absorb carbon dioxide, promotes sugar production, and strengthens the plant's immunity. Typical symptoms of potassium deficiency include chlorotic spots and yellow leaf edging. The following potash fertilizers are traditionally used:

• potassium sulfate, or potassium sulfate – 50%;
• potassium nitrate – 45%;
• potassium magnesium, or potassium and magnesium sulfate – 30%;
• potassium monophosphate – 33%.

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