Potassium fertilizers for tomatoes. Potassium monophosphate: instructions for use Potassium monophosphate foliar feeding norm

Experienced gardeners know that tomatoes can have trouble growing and bearing fruit. The problem can be solved by potassium monophosphate, the use of which for tomatoes is quite simple, as is the use of other mineral fertilizers. These measures are especially important for varieties that have such a feature as an underdeveloped root system. Feeding tomatoes can dramatically increase resistance to various diseases, increase productivity and improve the taste of the fruit. When applying fertilizers, be sure to take into account the acidity of the soil in which your plants grow. If this factor is not taken into account, then at best, fertilizing will be ineffective, and at worst, the vegetative process will be irreversibly disrupted.

The lack of potassium can be noticed by the appearance of the fruits: 1/3 of them may remain green. If the deficiency is significant, then the green unripe areas may be even larger.

Potassium for fertilizing tomatoes contains such a well-known product as potassium humate. The dosage is as follows: 1 tsp. dry powder or (15 ml in liquid form) should be diluted in 10 liters of water. This is a good remedy for increasing shoot growth, increasing frost resistance and an excellent immunostimulant.

• Potassium monophosphate is also popular, the use of which affects the taste of tomatoes. The potassium salt of orthophosphoric acid has an acidic pH. Due to the fact that the product is completely soluble in water, it is suitable for foliar feeding. Recommended concentration:
• when watering: 10-15 g per 10 liters of water;

foliar feeding: 1-2 g per 1 liter.

One of the good fertilizers is potassium sulfate. Tomatoes growing in alkaline soils will be especially grateful. The acidity of the solution is usually neutral. Concentration - 10 g per 1 l and per 10 l. But you should not abuse fertilizers with sulfur.

Nitrate: calcium, potassium and ammonium

• Potassium nitrate, or potassium nitrate, is popular. The fertilizer has a neutral pH, so there is much less risk of damaging the plant than if you use acidic fertilizers for tomatoes. It is important to use potassium nitrate when laying the first or second brush.
• when watering: 10-20 g per 10 liters of water;

Ammonium nitrate strengthens tomatoes, makes them stronger and improves immunity. Fertilizer is used before the ovaries appear on the bushes. To feed, add 10 g to the soil for every 1 m². Calcium nitrate will help if plant growth has slowed down, because calcium is responsible for the formation of a strong root system. Reviews of this nitrate are as one of the best fertilizers for acidic soils.

Nitrate is good for foliar feeding in the following concentration: 2 g per 1 liter. It protects against rot and various garden pests. For root feeding, dosage: 25 g per 10-15 liters of water.

First feeding of tomatoes after planting (video)

Fertilizer with phosphorus

The lack of phosphorus in plants is clearly visible: the lower part of the leaves acquires a purple tint. Fertilizers for tomatoes will help compensate for its deficiency: phosphate or superphosphate. Phosphate, as the name implies, contains only phosphorus, and superphosphate also contains nitrogen, magnesium, sulfur and calcium. But it is better not to use them on acidic soils. If you need to add superphosphate, you must first reduce the acidity of the soil with ash or lime (200 g of ash or 500 g of lime per 1 m²). At the same time, it is necessary to take into account that fertilizing should be applied no earlier than a month after such soil treatment, otherwise all beneficial properties will be lost and the effect will be extremely low.

Fertilizer is applied during planting of tomato seedlings, without deepening it too deeply, 20 g for each plant. Most of the phosphorus is used for fruit formation, so such phosphorus fertilizing should also be done during the fruiting period. Phosphorus is very poorly soluble in water, so to prepare the product you should take boiling water and pour 3 liters of water per 20 tbsp. l. For irrigation, be sure to dilute with warm water: 10 liters for every 150 ml of preliminary solution.

Security measures

When carrying out work related to dilution and application of fertilizers, take precautions! Be sure to use personal protective equipment, do not inhale solutions, and do not allow contact with unprotected areas of the skin.

Do not mix ingredients unless you are sure that it is safe and will not harm you or your plants. Remember that compliance with dosages is very important, otherwise your plants may get burned and you will lose your harvest. Follow the manufacturer's recommendations, which are indicated in the annotations. Keep powders, liquids and mixtures out of reach of your children and animals. If it gets into your eyes or stomach, be sure to consult a doctor and show him the package with the label.

Foliar and root feeding (video)

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When cultivating tomatoes, poor plant growth and fruiting may occur. To solve the problem, potassium monophosphate is used, the use of which for tomatoes does not cause any particular difficulties for gardeners. In particular, such substances are needed for varieties that have a poorly developed root system. Feeding tomatoes with such fertilizers improves disease resistance, increases productivity and has a positive effect on the taste of the fruit. However, such fertilizing must be done carefully, taking into account the acidity of the soil in which the plants are grown. If we neglect this factor, then either the efficiency will be low or the growing season will be completely disrupted. You should understand in more detail what kind of fertilizer this is and how to use it correctly.

When cultivating tomatoes, poor plant growth and fruiting may occur. To solve the problem, use potassium monophosphate

Potassium is an important mineral fertilizer in the process of growing tomatoes. The lack of this element in the soil can be judged by the fruits: a third of them may remain unripe. Some gardeners use a product such as potassium humate for tomatoes. When fertilizing a crop with such a preparation, the dosage should be as follows: 1 tsp. powder per 10 liters of water. This product will promote good shoot growth and increase resistance to frost and disease.

No less popular is potassium monophosphate, the use of which has a positive effect on the taste of fruits. It is convenient to use for foliar feeding, since it is completely soluble in water. The following concentration of the substance is recommended: for foliar use - 1-2 g per 1 liter, for irrigation - 10-15 g per 10 liters of water.

Potassium is an important mineral fertilizer in the process of growing tomatoes.

Potassium fertilizers have a great influence on the cultivation of various vegetable crops. Tomato fruits turn out beautiful and even. Feeding tomatoes with potassium monophosphate is highly effective. They are applied only in the evening, since the solution will remain on the leaves of the plants longer. The given concentration is enough for 4 tomato bushes. This substance cannot be used more than 2 times during the season.

It is worth mentioning another potash fertilizer - potassium sulfate. Plants will respond very well to such feeding. The solution has a neutral reaction. To prepare the composition, dilute 10 g of powder in 10 liters of water.

Phosphorus-potassium fertilizers (video)

When and How to Apply Monopotassium Phosphate

Before planting tomato seedlings in open ground, a sufficient amount of organic and mineral fertilizers must be added to the soil to make it nutritious. Among these we can distinguish wood ash, humus and urea. When the plants take root, you will need to provide them with potassium and phosphorus fertilizers. However, nitrogen fertilizers should not be applied during this period.

At this stage, it is most effective to use ash-based fertilizer by preparing a liquid solution, which will ensure good plant development and the formation of flowers and fruit ovaries.

Quite often you can hear from summer residents and gardeners that tomatoes are blooming, but there are no ovaries. What is the problem? Here are the main reasons:

• the seedlings were planted too early;
• rare watering;
• untimely application of nitrogen fertilizers;
• phosphorus fertilizers were applied in insufficient quantities;
• low quality seeds were used.

Before planting tomato seedlings in open ground, a sufficient amount of organic and mineral fertilizers must be added to the soil to make it nutritious

In this situation, potassium monophosphate, which contains 50% phosphorus and 33% potassium, is very helpful. Dilute the substance according to the above ratio (10 g per 10 liters of water). Such fertilizers are very useful for tomatoes during the flowering period. They are introduced by foliar method. When fruits begin to form, the plants must receive balanced nutrition. In this case, it is useful to add, in addition to potassium and phosphorus, nitrogen, i.e. provide tomatoes with a full range of nutrients.

The use of nitrate and phosphorus

Mineral fertilizers such as potassium, calcium and ammonium nitrate are also used to feed tomatoes.

Potassium nitrate is characterized by neutral acidity, which reduces the risk of damage to plants, unlike the use of acidic fertilizers. This product is applied during the formation of the first or second brush. The concentration should be as follows: for foliar feeding - 10 g per 1 liter of water, and for irrigation - 10 g per 10 liter of water.

Ammonium nitrate promotes the growth of stronger seedlings and has a positive effect on plant immunity. It is used before the ovaries appear on the bushes. When fertilizing, 10 g of substance per 1 m² is added to the soil.

If plants experience slow growth, then calcium nitrate, which contains 19% calcium and 13% nitrogen, will come to the rescue. Calcium promotes the formation of a good root system. Reviews about this type of nitrate indicate that it is one of the best fertilizers for soils with high acidity, unlike urea, which acidifies it.

Plants should also not lack phosphorus, as can be judged by the lower leaves on the bushes, which acquire a characteristic purple color. The situation can be corrected by adding fertilizers such as phosphate or superphosphate.

Phosphate contains only phosphorus, while superphosphate also contains magnesium, sulfur, calcium and nitrogen. But you need to be careful with application, since it is not recommended to apply such fertilizers on acidic soils. If there is a need to add superphosphate, then first take measures to reduce the acidity (for example, with lime at the rate of 0.5 kg per 1 m²). In this case, fertilizer is applied no earlier than a month after the soil has deoxidized. Otherwise, the effectiveness of such feeding will be extremely low.

Fertilizer is applied at the time of planting the crop under each bush (20 g), and there is no need to deepen it too much. It is worth noting that a large amount of phosphorus is consumed during fruit formation. Accordingly, fertilizing with phosphorus fertilizers is also carried out during the fruiting period.

Use of mineral supplements

Mineral fertilizers can be applied as both the main food and fertilizing in the spring and summer.

• Each battery has its own application rules, but there are also general ones that should not be neglected:
• You cannot use containers that are used for food purposes;
• when feeding roots, you need to avoid getting the solution on the plant to avoid burns;
• when applying fertilizers in dry form, they must be immediately embedded in the soil, but not deeply;
• if there is a lack of nitrogen in the soil, potassium and phosphorus fertilizers should be applied only in combination with the missing element;
• When applying mineral fertilizers together with organic ones, which is the most effective way, the dose of mineral substances should be reduced by 3 times.

Mineral fertilizers can be applied as both basic nutrition and fertilizing in the spring and summer.

If you feed the plants in accordance with the recommendations given, they will bear fruit well.

Potassium monophosphate is an effective phosphorus-potassium fertilizer used for all vegetable crops at different stages of development. The substance is highly soluble in water and does not contain sodium, chlorine or other impurities. The phosphorus content is inferior to superphosphate. In terms of mass fraction, K is superior to potassium nitrate, potassium sulfate and potassium chloride. The fertilizer formula is KH2PO4.

Features, advantages and disadvantages

Externally, the fertilizer is white granules or powder. At +90 °C it dissolves in water by 84%, at +20 °C - by 23%. The composition of the fertilizer is potassium monophosphate: 50% P2O5 (phosphorus oxide) and 33% K2O (potassium oxide).

Important: calcium monophosphate is not an analog or substitute for calcium monophosphate, but a feed additive. It is not used for feeding plants or in the garden in general.

In agriculture, potassium monophosphate is used in large and small areas. In gardens and summer cottages, the use of this fertilizer is more than justified. Potassium monophosphate is not a cheap fertilizer, but strictly dosed use eliminates this disadvantage. Benefits of fertilizer, which a vegetable grower needs to know about:

• optimal ratio of phosphorus and potassium;
• good solubility;
• stimulation of the formation of side shoots with flower buds;
• digestibility by all parts of the culture;
• no risk of overdose;
• possibility of use within the same solution with pesticides;
• the ability to protect crops from fungal diseases, including powdery mildew;
• minimum ballast components;
• no effect on the acid-base composition of the soil;
• positive effect on beneficial microorganisms living in the soil.

Fertilizing with potassium monophosphate reduces the likelihood of soil drying out even with scanty watering. Considering the cost of water, this factor often becomes decisive when choosing a phosphorus-potassium fertilizer.

Cons of monophosphate:

When planning to use a substance to fertilize flowers, you need to consider two points. Cut flowers are less marketable, therefore, business profitability decreases. Plants begin to branch heavily, resulting in cut shoots that are too short. Also, you should not fertilize indoor flowers with this drug that are prone to slow development, including:

• dodecatheons;
• cyclamens;
• orchids;
• abutilenes;
• gloxinia;
• succulents;
• azaleas;
• Strepocarpus.

There should be no negligence in relation to weeds. There are known cases where, as a result of excessive application of monocalcium phosphate, giant weeds, more like trees, grew on the site. It can be very difficult to remove such specimens, especially if they are covered with thorns.

When and how to use

The maximum effect of fertilizer is observed in the first half of the growing season. In spring, monophosphate is applied to fruit trees and shrubs. When planting seedlings, vegetable crops are watered with the solution. Then they feed before and during flowering.

Methods of application- directly into the soil or in the form of foliar feeding. The substance can be mixed with fertilizers other than calcium and magnesium. Good results are achieved when combined with nitrogen-containing preparations.

Feeding seedlings

Vegetable crops in the initial stage of growth are watered with a solution prepared from 10 liters of water and 10 g of fertilizer. It is recommended to water the flowers growing in the room and in the front garden with the same liquid. The rate of application of monopotassium phosphate in open ground is 5−7 liters per 1 sq. m. m., for indoor flowers, 250 ml per specimen is enough.

Processing of vegetable crops

Immediately before flowering, vegetables are watered with a solution of 10 liters of water and 20 g of the drug. Before budding, 4 liters of liquid are consumed per 1 square meter. m, after which the norm is increased to 6 liters per 1 sq. m. In addition to watering, it is recommended to spray the plantings with the same solution using a sprayer. Treatment is best done before sunset so that the solution does not evaporate from the leaves before it has time to act.

Tomato fertilizer

Tomatoes are fed 2 or 3 times during the growing season. There must be a break of at least 20 days between two applications. A nutrient solution is prepared from 10 liters of water and 15 g of the drug. For 1 adult bush, 2.5 liters are consumed. If weather conditions contribute to the rapid growth and good development of tomatoes, the break between feedings is extended to 25 days. Additionally, you can treat the leaves with a more saturated solution (20 g of fertilizer per 10 liters of water). After rain, it is recommended to carry out a similar spraying to provide tomatoes with protection from fungal infections.

Application on cucumber plantings

For cucumbers, apply a solution of the same concentration as for tomatoes. The consumption is similar, but you should additionally pay attention to the condition of the fruit. If they develop well, have a characteristic color and correct shape, no additional measures are required. When some cucumbers form crooked, ugly and too small, this is a sure sign that there is not enough potassium in the soil. In this case, boarding urgently fed by spraying.

If there is a delay in fertilizing, the fruits will become bitter, and then no measures will help. In such cases, timely fertilizing is more important than watering: when the drug is applied in liquid form, the soil is moistened and the cucumbers receive enough moisture. Important: at least 2 weeks must pass between two feedings.

How to feed root vegetables

Carrots, beets, rutabaga, horseradish, radish and others Root crops are fed only by spraying a nutrient solution over the leaves. If you pour fertilizer under the root, this will only lead to the fact that the underground part will grow greatly and will be rough and tasteless. The commercial quality of the products will be low. The working solution is adjusted as follows: add 30-50 g of granules to 10 liters of water and dissolve. Use immediately after preparation. Onions, garlic and other crops whose edible parts are in the ground are fed in the same way.

Features of feeding grapes

It is better not to fertilize the vineyard with monopotassium phosphate, except in cases where the vine experiences a severe potassium deficiency. At the same time, the winegrower must be aware of what he is doing.

In practice, grapes more often suffer from a lack of magnesium, so it is better to replace potassium phosphate with potassium magnesium. It is applied in the fall so that the nutrients have time to dissolve and be absorbed by the plants. In unfavorable years, they feed more intensively and earlier than usual, since potassium magnesia dissolves rather slowly.

Processing berry fields and fruit trees

Bushes and trees can be sprayed with monosulfate or watered. The solution is prepared more concentrated than for vegetables: 30 g of the drug per 10 liters of water. Consumption for bushes is in the range of 7-10 liters per 1 sq. m. Trees are fed at the rate of 20 liters per 1 sq. m. When root feeding, you need to try to ensure that the solution gets as close to the trunk as possible, distributing it over the area where the root system is located.

Application under flowers

Fertilizing plants planted in flower beds and front gardens begins when buds begin to form. The favorable period for applying fertilizer lasts until the crops bloom. If you want flowering to occur faster, it is useful to feed the seedlings in the phase of 3 true leaves. Instructions for preparation and use:

• dilute 50 potassium monophosphate in 10 liters of warm water;
• water the plants at the root at the rate of 4 liters per 1 sq. m;
• after a few hours, loosen the soil.

After two weeks, another feeding is done, using the same amount of liquid, only the amount of the drug should be 70-100 g per 10 liters. For spraying, prepare a nutrient solution of 5 liters of water and 10 g of fertilizer.

Flowers planted in hanging pots and flowerpots are fed taking into account their need for potassium. For example, phloxes need less of this element than petunias. For the latter, the norm is 35 g per 5 liters of water at a consumption of 250 ml per plant. Since petunias are one of the most common flowers, you can take as a basis the instructions intended for them:

• in the seedling phase, add 1 tsp. per plant or 3 liters per sq. m at a concentration of 25 g per 5 liters of water;
• after 12 days, feed with the same solution, but the consumption is increased to 6 liters per 1 sq. m or 2 teaspoons per plant;
• At the beginning of flowering, plantings are watered at the rate of 10 liters per 1 sq. m (50 g of monophosphate per 5 liters of water).

After each rain, ampelous crops are sprayed on the leaves. The working solution is prepared from 1 g of fertilizer and 10 liters of water. When growing crops in a suspended state, you need to keep in mind that nutrients are washed out faster than under natural conditions. Therefore, you should additionally use liquid complex fertilizer for flowers.

Precautionary measures

Monophosphate is stored as indicated on the package. The possibility of access by animals and children should be excluded. The room where the fertilizer container is located must be dry and well ventilated. You can work with the drug only with gloves. In case of contact with eyes or skin of hands, problem areas should be rinsed with running water. If accidentally swallowed, induce vomiting and seek medical attention.

No one believes that in the garden I only use organic matter and monopotassium phosphate. I always harvest raspberries and gooseberries to the envy of my neighbors; I have enough to make compotes and jams and sell them as well. I would like to give advice to gardeners: if you use this fertilizer, add additional nitrogen, for example, compost or rotted mullein.

Zinaida Valerievna, Vologda.

I have a large collection of Uzumbara violets. Both neighbors and friends are surprised how I manage to care for so many flowers. And I just feed them monopotassium phosphate. They grow well, bloom profusely and never get sick. I recommend it to all flower growers.

Nadezhda Igorevna, Arkhangelsk

Good fertilizer, you just need to look at who the manufacturer is. We buy potassium monophosphate “Buyskie Fertilizers”, we are satisfied with the quality. Suitable for all major crops, but it is better not to apply it in the fall - the effect is zero.

Vladimir Andreevich, Kostroma region.

In order for the plantings at the dacha to produce a bountiful harvest and the flowers to please the eye for a long time, the plants need to be fed. Thanks to the correct and timely application of fertilizers, they become stronger and better resist diseases. There are a large number of mineral fertilizers on the market, from which you can choose the most suitable one. One such fertilizer is potassium monophosphate. This tool is easy to use, but has both pros and cons. However, often feeding with such a drug gives excellent results. It is used in feeding trees, shrubs, vegetables and even indoor plants.

Explanation of the popularity of potassium monophosphate

By purchasing the drug and using it to feed plants, people strive to achieve the following goals:

More vitamins and sugars accumulate in vegetables, berries and fruits, which improves their taste. Due to the fact that this fertilizer helps to increase the yield of garden and vegetable crops, it is used not only by ordinary summer residents, but also in large farms specializing in growing vegetables and fruits. The drug can also be useful at the stage of growing seedlings.

For those involved in floriculture, fertilizer can also be useful. This applies to both crops that grow in open ground and indoor flowers. Spraying with a solution of potassium monophosphate will help the earlier appearance of buds, abundant and long flowering. Feeding with this fertilizer makes it possible to protect seasonal plantings of flowers in flowerpots, flower pots, and so on. If the plant suffers from acute potassium starvation, the drug will be indispensable.

This product is used to feed trees and shrubs. As a rule, plants are watered with a solution. The procedure stimulates their growth and the appearance of new shoots well.

Fertilizer properties

Potassium monophosphate or monopotassium salt of orthophosphoric acid is a white powder; in stores you can find fertilizer in granules that has a beige tint. The powder dissolves well in water.

The drug is considered a highly concentrated potassium-phosphorus fertilizer, although there are also products more saturated with these elements. This is explained by the fact that it consists of 33 percent potassium and 52 percent phosphate. Moreover, it does not contain such undesirable elements as chlorine, sodium and heavy metals. Such purity means that the use of the drug cannot harm the plant. At worst it will decrease feeding efficiency.

In order to fertilize the plantings, it is better to buy the product in granules. The fact is that the powder can only be used as a solution. And the granular form allows not only to dilute monopotassium in water. The product can be mixed with water of any quality.

The fertilizer is very affordable, so summer residents regularly buy it. Although stores sell drugs that contain this chemical compound.

Advantages and disadvantages of potassium monophosphate

Fertilizer is excellent for feeding plants in small areas using manual labor. Among the advantages of the drug are:

1. All parts of the plant absorb the beneficial substances contained in the product.
2. Good absorption of fertilizer is facilitated by the fact that the mixture dissolves well in water.
3. There is no need to be afraid to overfeed the plantings with monopotassium; this will not cause burns on the leaves and they will not become deformed.
4. The drug has no side effects.
5. The fertilizer is compatible with pesticides. You can even mix solutions in one container and simultaneously treat plants with them.
6. The product is suitable for increasing soil moisture and saving water when watering. Monokassium interacts well with soil microflora, which is why it is often used in greenhouses. When fertilized in a timely manner, the soil does not dry out.

The large number of positive qualities of the product make it a popular drug. But this fertilizer also has its drawbacks:

Nevertheless, fertilizer has more advantages than disadvantages, so its use in dacha farming has prospects. It is easy to use, safe and improves crop production.

Methods of feeding plants

There are different ways of feeding. Before you start processing, you must carefully read the instructions on the package with the drug. Typically, potassium monophosphate is used in foliar feeding. To do this, powder or granules are diluted in water and watered over the plant. You can also spray the plantings with the solution.

Processing should be done in warm, but not hot, weather. It is better to fertilize in the evening so that the composition does not evaporate under the influence of sunlight. It is believed that the optimal effect is achieved when transplanting seedlings into the ground or during spring treatment.

Before starting work, it is necessary to prepare the solution. Fertilizer concentration depends on the type of fertilizing:

1. Regular watering of the beds is done with a solution obtained by mixing 20 grams of the drug and 10 liters of water.
2. Trees and shrubs are treated with a more saturated mixture. Here you will need 30 grams of fertilizer per bucket of water. Plants are usually watered with this solution.
3. To fertilize flower crops, seedlings, and indoor plants, a weak solution is used: 10 grams per 10 liters. The soil is treated with this mixture.

In addition to watering, spraying is also used. It improves plant growth and fruiting. When tomatoes are treated with this product, ripening will be more uniform.

You should remember safety precautions when working with fertilizer. During all procedures, you must wear rubber gloves and avoid getting the solution on your skin. After working with monopotassium, you should wash your hands and face well. The product itself should be stored in a ventilated area and not come into contact with food.

Plants are fertilized with the drug twice a year.. There must be a time interval of at least 14 days between procedures. It is possible to use this drug simultaneously with nitrogen fertilizers, which will have a positive effect on the growth of plantings.

In gardening, situations arise when heavy rains wash away beneficial substances from plants and soil. Here, in order to avoid potassium starvation, additional feeding should be done with a weak solution.

Features of feeding different crops

Despite the versatility of monopotassium phosphate, Plants should be treated taking into account their characteristics. So, grapes usually do not need such a preparation, however, if the season was cold, then you should feed the vine in the fall before wintering. The vine can be watered or sprayed.

Cucumbers are fed in the same way as tomatoes. But root crops should not be watered with the solution; they can only be sprayed.

When feeding flowers, weak solutions are used. The first time the flower must be fertilized when the first buds appear, and the second time treatment is required during flowering. In some cases, watering with the mixture can cause earlier flowering. The dosage of flowers may vary depending on the type.

When watering, you should remember the existing standards. Vegetable and berry plantings need 3-6 liters of solution per 1 square meter, depending on the stage of development. Flowers - from 5 to 10 liters. Fruit trees need plenty of water - up to 20 liters, bushes - 7-10 liters per 1 square meter.

Material prepared by: Yuri Zelikovich, teacher of the Department of Geoecology and Environmental Management

© When using site materials (quotes, tables, images), the source must be indicated.

Potassium monophosphate (monopotassium phosphate) is a ballast-free potassium-phosphorus fertilizer. Chemical formula KH2PO4; name according to the chemical nomenclature of potassium dihydrogen orthophosphate (monocassium salt of orthophosphoric acid). The structural formula is given on the left in Fig. Density in monocrystalline form 2.34 g/cu. cm. Solubility in water at 20 degrees Celsius 22.6% by weight; at 90 degrees – 83.5%, i.e. Potassium monophosphate is a highly soluble substance. Chemically pure potassium monophosphate - colorless crystals. Release forms for agrochemicals: powder or granules of light brownish or beige color, in the center in Fig. A pronounced yellowish color is evidence of the presence of iron or free sulfur impurities; such a drug is a manufacturing defect.

The composition of potassium monophosphate on factory packaging (on the right in the figure) is given in terms of the active ingredients, because in soil moisture in the presence of humates, potassium monophosphate completely dissociates, and radicals (residues) come into contact with air oxygen. In fact, the active substances in potassium monophosphate are K- – 28% and P+ – 23%. Therefore, the statement that potassium monophosphate is one of the most concentrated potassium-phosphorus fertilizers is incorrect. In potassium it is superior to potassium chloride, potassium sulfate and potassium nitrate; for phosphorus - superphosphates.

Note: It is better to purchase potassium monophosphate in granular form. The powdered drug can only be dissolved in water. When mixing potassium monophosphate powder with water of increased hardness, it sometimes sinteres. The granular preparation can be dissolved and mixed with ordinary tap water, as well as well water, spring water, from an Abyssinian well on the site, etc.

Advantages and disadvantages

Nevertheless, the use of potassium monophosphate in agricultural technology is more than justified, especially on small and medium-sized areas if there are possibilities for manual individual processing of plants. In such conditions, the relatively high (but not excessively high) cost of the drug is more than compensated by the increase in yield.

Potassium monophosphate as a fertilizer has a trace. advantages:

1. The ratio of active K and P in the preparation is optimal for maximum fruiting, as well as increasing plant resistance to diseases, pests and frosts;
2. Potassium monophosphate, more than other phosphorus-potassium fertilizers, promotes the formation of lateral shoots with peduncles, which is essential for flowers, except for cutting (see also below);
3. High solubility causes rapid migration of active substances and ease of their absorption by plants;
4. Potassium monophosphate is absorbed by all parts of plants;
5. It is almost impossible to overfeed plantings with potassium monophosphate; this advantage is a consequence of one of its disadvantages, see below;
6. Potassium monophosphate is fully compatible with pesticides, up to the preparation of a single tank solution for complex treatment;
7. Potassium monophosphate itself is a good means of preventing and combating powdery mildew and other diseases. other fungal diseases;
8. The absence of ballast substances guarantees the absence of side effects from the fertilizer;
9. Potassium monophosphate has virtually no effect on soil acidity;
10. Potassium monophosphate is also beneficial for beneficial soil microflora. This is very important for greenhouse farming: drying out of the soil with seemingly sufficient watering in greenhouses regularly fed with this fertilizer is a rare exception, because microorganisms involved in soil structuring are in comfortable conditions.

Note: Point 10 is also important because it allows you to reduce water consumption for humidifying the greenhouse. Given the current tariffs for it, you will agree, this is significant.

About compatibility with nitrogen

Plants will respond well to phosphorus and potassium only if they have healthy, powerful green mass, which requires nitrogen. There are no serious contraindications to the use of potassium monophosphate together with nitrogen fertilizers, but it is better not to take risks by preparing a common solution of both. The high activity of potassium monophosphate makes it possible to reduce the gap between potassium-phosphorus and nitrogen fertilizing to a minimum of 2-5 days; the wetter the weather, the shorter the gap. Nitrogen should be given after phosphorus and potassium, except for nitrogen-fixing plants: legumes, clover, alfalfa.

Note: Usambara violets Saintpaulia are also nitrogen fixers. They can be fed with monopotassium phosphate alone. If signs of nitrogen starvation appear, it is useless to add nitrogen; incorrect maintenance conditions are to blame - little light, heavy, poorly permeable soil or acidic soil.

An excellent mineral fertilizer in general, potassium monophosphate is not without its drawbacks:

1. Potassium monophosphate does not accumulate in the soil and decomposes very quickly, so fertilizing with it is carried out only in solutions (see below). Adding solid potassium monophosphate to the soil will not harm the plants, but it will not do any good - all the fertilizer will be lost;
2. As a consequence of the previous etc., potassium monophosphate is not suitable for pre-winter preparation of plantings in open ground, except in certain cases, see below;
3. Also, due to point 1, potassium monophosphate is most effective in the warm season of a favorable year - not hot and moderately humid. In greenhouses - with sufficient lighting and regular ventilation;
4. Another negative consequence of point 1 is that weeds taste and use potassium monophosphate no less than cultivated plants. Therefore, its use in the garden or vegetable garden can only be recommended to cultivated owners who have enough time and means to control weeds. At a weekend dacha, weeded occasionally, potassium monophosphate will cause the area to become overgrown with anything other than what is needed;
5. Potassium monophosphate is hygroscopic and, when wet, loses its properties. Working solutions are unstable in air and light. Therefore, you need to purchase the drug in packages suitable for single use, and use the working solution immediately after preparation.

Potassium monophosphate is completely incompatible with magnesium and calcium fertilizers, which seriously limits its use for certain crops, see below;

Note: The author once saw, on a plot of land whose owners madly relied on potassium monophosphate, a thistle 4.5 m high (!) and with a stem as thick as a healthy man’s arm. Vo grew big thanks to tomatoes and potatoes! The hedge trimmer didn't take it, so I had to cut it down. The core was as hard as ivory, and the thorns would make a good rake. I imagined plantations of such mutants for technical purposes - interesting, but not in the countryside for winter help.

Monopotassium phosphate and grapes

Grapes need magnesium more than other berry plants, so under normal conditions we do not recommend potassium monophosphate for fertilizing vineyards. Typically, grapes are fed with potassium magnesia in the second half of summer and in preparation for winter. But it is not a particularly active fertilizer: it migrates in the soil and is absorbed by plants slowly, but it leaches well. Therefore, if the year turns out to be cool and wet, the vines do not have time to get enough potassium, winter is difficult, and the harvest the next year is poor. In this case, intensive pre-winter preparation of grapes using potassium monophosphate will be justified, see video:

Video: feeding grapes with potassium monophosphate before winter

Indications for use

Based on the above-described properties and characteristics of potassium monophosphate, it is recommended to use it for feeding cultivated plants:

• For seedlings of garden crops in average weather conditions and favorable years. In unfavorable years, when planting in the ground is delayed, it is better to stimulate root formation at the box-pot stage with a limited amount of nutrition with rootstock.
• For more abundant flowering, reduced ovary drop and better fruiting - all garden food crops.
• Ornamental open ground crops - for more abundant and longer flowering.
• For seasonal outdoor flowers: hanging, potted.
• For emergency foliar feeding of outdoor and indoor plants in the presence of signs of acute potassium starvation: browned, “rusted,” wrinkled and curled edges of leaves.

Seedlings, garden and vegetable garden

The standard regulations for the application of potassium monophosphate to horticultural crops and seedlings in average and favorable years in the Central Belt of the Russian Federation are given in the figure:

The dosage within the specified limits should be selected according to the habit (large, small, thin, lush) and the speed of plant development (early ripening, late ripening). Errors within the limits of the indicated doses are insignificant, but an experienced plant grower, using them, can achieve the maximum yield in a given year with minimal costs for agrochemicals.

The optimal effective dosage of potassium monophosphate for foliar feeding is 0.05% (5 g per 10 liter bucket of water); the minimum for spraying decorative potted and hanging flowers after a rainstorm and in other cases (see below) is 0.02% (2 g per bucket). The same dosage is valid for planned foliar feeding in productive years. Maximum, for watering fruit trees after heavy rain or prolonged rains – 0.3% (30 g per bucket).

Note: Emergency fertilizing with potassium monophosphate on the leaves in a minimum dosage after heavy rains or heavy rains should be carried out to avoid oppression of plants accustomed to a complete potassium-phosphorus diet, because Heavy/long rains wash away potassium not only from the soil, but also from the apical (above-ground) parts of plants. For comparison, a person who is accustomed to fasting can tolerate malnutrition more easily than someone who eats plenty every day.

The rules for watering and spraying are general: in the evening, preferably on a cloudy day, or in the morning until light. Watering - into pre-moistened soil. Consumption rates for irrigation solution:

• Fruits and vegetables in the early stages of development (before budding) - 3-4 liters per 1 sq. m of plantings.
• They, at the maturity phases, are 5-6 liters for the same area.
• Decorative flower crops - 5-10 liters per 1 sq. m of planting depending on the habit.
• Berry bushes - 7-10 liters per 1 sq. m of area shaded at midday. Water at the roots, not between the rows!
• Fruit trees - 15-20 liters per 1 sq. m of tree trunk circle.
• Ornamental trees - 20-30 liters for the same area.

Spraying - with small “foggy” sprays until the leaves are filmy surface moistened; the appearance of rolling drops is unacceptable. For certain crops, some specific features of fertilizing with potassium monophosphate apply.

Tomatoes

Watering with a 0.15% solution of potassium monophosphate (15 g per bucket of water) for tomatoes should be carried out no more than 2 times per season with an interval of at least 2 weeks. Watering rate is a bucket of working solution for 4 bushes. In productive years, it should be extended to 3 weeks or more in accordance with the observed phases of plant development (see standard regulations). In this case, spray the leaves with a 0.02% solution in the intervals between waterings. The same solution is used for emergency spraying after heavy rains, see above.

cucumbers

Cucumbers are fed by watering with a solution of potassium monosulfate in the same doses and on the same schedule as tomatoes. The working solution for spraying is also 0.02%, however, foliar fertilizing with potassium and phosphorus for cucumbers should be carried out with an eye on the developing fruits. A normally ripening cucumber is straight and thicker at the petiole than at the tip. If the fruits, starting from the ovaries, are curved and/or pear-shaped, they lack potassium, they need to be fed by spraying. Foliar feeding of ripening cucumbers takes priority over fertilizing by watering, because If the cucumbers turn brown from a lack of potassium, there is no way to fix it. That is, if, for example, on the next watering is scheduled for a week, but the cucumbers are crooked, fertilizing watering needs to be postponed, because... the time interval between fertilizing with potassium monophosphate should be at least 1.5-2 weeks.

Potatoes, root vegetables, onions, garlic

It is advisable to feed potatoes with potassium monophosphate only by spraying on the leaves. Fertilizer irrigation will lead to excessive growth of the root system by reducing the number, weight, taste and boiliness of tubers. Solution – 0.02-0.05%; processing - twice per season according to regulations. In exactly the same way and for the same purpose, root crops and bulbous edible plants are fed with potassium monophosphate.

Fruit and berry plants

Fruit trees and berry bushes are regularly fed with potassium monophosphate, on the contrary, mainly by watering. Emergency/unscheduled feeding of the crown is carried out in productive years and after heavy rains, see above. Spray only the vegetative (green) parts, trying to get more of the solution onto the undersides of the leaves. Watering is carried out 1.5-2 hours after the treated area is well moistened. You can water trees and shrubs with potassium monophosphate in the morning, as long as the ground is moist, but not in rain or fog - most of the fertilizer will be lost. Mature stably bearing fruit trees can be watered with a 0.2% solution (20 g per bucket of water).

Monopotassium phosphate and flowers

Fertilizing flowers in flower beds and lawns with potassium monophosphate is carried out at the beginning of the buds opening and when entering the phase of abundant flowering. In a favorable year, it is possible to achieve early flowering by watering the sprouts in the phase of 3-4 true leaves with a 0.05% solution at the rate of 3-4 liters per 1 square meter. m of planting. For irrigation in the stages of active vegetation, a 0.07-0.1% solution is used. Spraying, if necessary (see above), is done with a 0.02% solution.

Potted and ampelous outdoor flowers are fed with potassium monophosphate in the same way as petunias (see below), but the dosage is adjusted (not the consumption rate of the working solution!) in accordance with the comparative need of both for potassium; it is obtained according to the manuals for gardeners. For example, phlox needs approx. 3/4 potassium compared to petunias. In this case, the working solution is prepared not 0.1%, but 0.07%.

Petunias

These flowers are sometimes called survivors: faded, degenerate petunias can be seen growing on dust banks under the walls of houses or in the city from cracks in the asphalt. However, luxurious varietal petunias are quite sissies; especially hanging ones (in hanging flowerpots) and grown in vertical flower beds. Accordingly, the schedule for feeding petunias with potassium monophosphate looks like this:

• Seedlings, 2-3 true leaves – 0.05% solution, 2-3 liters per 1 sq. m or a teaspoon per plant.
• 10 days later - 2 weeks after picking or landing in place - 0.07% solution, 5-6 liters per 1 sq. m.
• At the beginning of flowering - 0.1% solution, 10 liters per 1 sq. m. m.
• Ampelous and vertical flower beds - after a rainstorm, spray with a 0.01% solution (1 g per bucket of water) regardless of the planned fertilizing schedule.

In general, ampelous petunias require especially careful fertilization and care, because nutrients from hanging flowerpots are leached (washed out) instantly compared to open ground. Here you can’t get by with potassium monophosphate alone; you need to use a variety of them, see next. video lesson.

Video: about fertilizing petunias