Superphosphate - application. Double superphosphate: application, formula and price of fertilizer
Modern gardeners are well aware that it is impossible to get a generous and high-quality harvest without fertilizers. In the complex process of growing plants for abundant flowering and fruiting respond phosphorus-containing substances. In the article we will tell you how to apply double superphosphate in spring and autumn, how to breed, application rates and reviews of leading gardeners.
Double superphosphate - mineral fertilizer with a high phosphorus content. The production is based on the interaction of phosphoric acid with raw apatite ore. As a result, a substance is formed in which the nutrient element takes a form accessible to plants (find out → ) .
The composition of the fertilizer and its effect on crops in different periods of the growing season
Consultation specialist
Another way to achieve complete dissolution is to add humate containing phytosporin to the water ( see →).
Before use, the base solution is diluted with water, in a ratio of 150 ml per 10 liters of water. 500 g is added to it wood ash, (better from birch firewood), 200 ml of infusion of any humus. It is needed as a source of nitrogen; without it, phosphorus is not absorbed by plants.
This supplement is well suited for spring fertilizer rooted seedlings of many garden crops.
It is given in the following doses:
The norm of nutritious watering for seedlings of beets, carrots, turnips, radishes, celery -
1 l per 1 m / p of each row.
The next top dressing of tomatoes, eggplants, peppers, cucumbers and potatoes is repeated at the end of flowering. The dosage is the same as for the first session.
Fertilizing fruit trees and berry bushes
In the spring, after the snow melts and the soil is cleared of plant residues, every trunk circle a tree or shrub contribute double superphosphate in the following quantity:
- for young trees up to 5 years - 20 - 30 g
- for adult trees in the fruiting stage - 40 - 60 g,
- For berry bushes- currants, gooseberries, yoshta - 20 - 30 g
- for raspberries - 30 - 40 g per 1 m 2 rows.
Powder or granules are evenly distributed on the soil away from the trunk of a tree or shrub shoots. Best at the level where the crown ends.
The fertilizer is evenly mixed with moist soil, to a shallow depth.
For the preparation of woody plants by winter, a mixture of fertilizers is applied to each trunk circle:
- Double superphosphate - 20 - 60 g;
- Potassium chloride - 20 - 30 g. ( see →);
- Humus or compost - 0.5 - 1 kg ( see →).
The amount depends on the size of the tree or bush.
foliar top dressing
It is carried out for better assimilation by plants nutrients, as well as when a deficiency of an element is detected. The fact that there is not enough phosphorus in the soil is signaled by crops with the following symptoms:
- The leaves become small, lose turgor (elasticity), look like wilted;
- The upper side of the sheet becomes bluish, the lower part of the plate turns red;
- Often the leaves curl at the edges, dry out and fall off prematurely;
- One of characteristic features- reddening of leaf petioles and stems. They acquire a red cherry hue;
- When blooming flower buds appear small flowers, pale color. They crumble quickly. The ovary is formed poorly, even if it has formed, most often it immediately crumbles.
Symptoms are associated with a lack of nitrogen, because without it, phosphorus is not absorbed.
To quickly reanimate the plants, they are sprayed with a solution prepared for root watering. But, dilute its saturation three times less. That is, the base solution will need 50 g per 10 liters of water.
Leaves and stems are processed from all sides in the evening.
Rubric: "Questions and answers"
Question number 1. How can the situation be corrected if more superphosphate was added than it should be?
In this case, do not water the crops, although for a week. If the weather is too hot, then it is better to arrange shading, and maintain the temperature + 22 0 - +25 0.
Question number 2. Is it possible to apply double superphosphate and ash together?
It is possible, only you need to take into account that the application rate for each type of fertilizer is halved.
A serious mistake of gardeners when using double superphosphate
Use fertilizer on acidic soils without prior neutralization. If the soil pH is less than 5.5, then phosphorus-containing compounds become inaccessible to plants. To normalize the acid-base balance, calcium-containing substances are added:
- Lime,
- Dolomite flour.
Neutralization is best done in advance, for example, in autumn, and double superphosphate in spring. At the same time, these substances are not used, because when they react with each other, they cause harm to plants.
Feedback from an experienced gardener
Ekaterina Maksimovna (Torzhok, Tver region)
I am careful with mineral fertilizers and try not to use them in the garden. But for my collection of roses, I do not regret double superphosphate. I think that only thanks to him, my beauties bloom brightly and magnificently every year, from early summer to autumn.
Superphosphate acquired wide application, as a fertilizer for garden, vegetable crops, trees, shrubs and indoor flowers. It is applied to the soil in spring, summer and autumn. There are several varieties of this fertilizer, which differ in composition.
The main component of fertilizer is phosphorus. Its share is from 20 to 50%. Phosphorus oxide is in a water-soluble form, which is a huge advantage of fertilizer. You can make liquid top dressing, as a result of which useful material quickly get to the roots of plants.
Depending on the type, phosphate fertilizer may contain:
- nitrogen;
- sulfur;
- molybdenum;
- calcium sulfate.
Phosphorus in the composition is most often in the form of phosphoric acid and monocalcium phosphate.
How to understand that plants need phosphorus?
Phosphorus is needed by all plants for normal development and growth. Without it, no culture will grow and bear fruit.
Signs of deficiency of this element:
- slow plant growth
- crushing leaves;
- changing the color of the leaf plate to a bluish-green or blue tint;
- twisting and falling of leaves;
- purple-purple or red spots on the lower leaf plates;
- poor fruit set with normal flowering;
- poor ripening, shedding of green fruits or their crushing.
Phosphorus is less readily absorbed low temperatures ah, therefore, early planted seedlings suffer from a deficiency of this substance more often.
Important. greatest need in phosphorus tests potatoes, cucumbers, carrots and cabbage. Less sensitive to a deficiency of a substance are nightshade, radish, beets and onions.
With a sufficient amount of phosphorus, the plant enters the fruiting phase faster, productivity increases, other useful macro- and microelements are better absorbed, the level of nitrates in vegetables and fruits decreases, and the taste characteristics of fruits improve.
Phosphate fertilizers also increase the immunity of crops, protect against diseases. Top dressing slows down aging, promotes the development of the root system.
Varieties of superphosphate
The composition of the fertilizer depends on the type of superphosphate. There are such varieties: simple, double, granular, boron, ammoniated, magnified, molybdenum. The dosage and composition of each type is different. When choosing a fertilizer, it is worth considering the needs of crops for nutrients.
Simple
Simple superphosphate contains:
- 10-20% phosphorus;
- 8-12% calcium;
- 10% sulfur;
- 8% nitrogen;
- 0.5% magnesium.
This non-concentrated water-soluble fertilizer is available in the form of a gray powder or granules. It is less effective than other varieties, but is much cheaper.
Most often, simple superphosphate is used by farms. Suitable for feeding legumes, cereals, bulbs, as well as potatoes, beets, carrots, turnips, radishes and other crops.
Double
Double Superphosphate is a concentrated water soluble fertilizer. It contains a large amount of water-soluble calcium, so useful substances are better absorbed by plants.
Fertilizer composition:
- 40-46% phosphorus;
- 20% nitrogen;
- 6% sulfur;
- calcium sulfate;
- zinc;
- copper;
- iron;
- manganese;
- molybdenum.
The fertilizer is suitable for all soils and plants.
Granulated
It is made from simple superphosphate. The powder is pressed and turned into 3-4 mm granules.
Granular superphosphate is more convenient to use. It dissolves more slowly in the soil, but is in a more accessible form for plants.
The composition includes up to 50% phosphorus and 30% calcium sulfate. This nutrient content is important for cruciferous, cereals, legumes and bulbs.
Ammoniated
This is a granular nitrogen-phosphorus fertilizer. In addition to the main components, its composition includes sulfur (about 12%) and calcium sulfate (up to 55%).
The fertilizer is most suitable for oilseeds and cruciferous plants, which need not only high doses of phosphorus, but also sulfur. It does not acidify the soil, so it is suitable for acidic soils. Another significant advantage is the good absorption of nitrogen by plants.
Ammonized superphosphate dissolves in water, therefore it is suitable for root and foliar dressings.
What soils to use?
The fertilizer is suitable for application to any type of soil, but it brings the greatest benefit to plants that grow on neutral or alkaline soils. With increased acidity, superphosphate turns into iron or aluminum phosphate. These compounds are not available for plant nutrition, so they will not be useful.
Often, cheap fertilizers contain impurities that contribute to the formation of indigestible phosphates. For acidic soil, it is necessary to choose only expensive phosphate fertilizers or pre-deoxidize the soil with lime or wood ash. For 1 sq.m. plot you need to make 200 g of ash and 0.5 kg of lime.
Important. Phosphorus fertilizer should be applied no earlier than a month after soil deoxidation.
You can safely use superphosphate on acidic soil as a preventive top dressing. Phosphorus will become available to plants next year.
Instructions for use
Superphosphate should be used according to the doses indicated in the instructions. It is not necessary to plant fertilizer in the soil, it is enough to scatter it on the surface of the soil before the rain.
In the garden
The use of superphosphate can be done in the following ways:
- apply to the soil in a dry form before planting;
- add to compost, humus, manure;
- sprinkle on the soil surface just before spring or autumn digging beds;
- prepare an aqueous solution and water the plants under the root;
- sprinkle on the surface of the soil during top dressing.
It is possible to use phosphate fertilizer in the garden in spring, summer and autumn, but preference should be given to autumn top dressing.
Important. The highest dose of phosphorus should be applied during flowering and fruiting.
The application rates for superphosphate are as follows:
- as a soil fertilizer - 40-50 g / m2. (on poor soils, the dosage can be increased to 100 g / m2);
- as a top dressing - 55-70 g / m2;
- for fertilizing seedlings during planting - 500 g per landing pit;
- root top dressing of trees - 40-70 g;
- planting potatoes - 3-4 g in each well or 20 g / m2. site;
- tomato fertilizer - 20 g for each plant (in spring and summer before flowering).
For vegetable crops, it is desirable to use simple superphosphate simultaneously with potassium and nitrogen fertilizers, double and granular - with potash top dressing.
Important. Instructions for use states that superphosphate cannot be used simultaneously with urea, ammonium nitrate, lime and chalk. There should be at least 7 days between feedings.
Best for seedlings root top dressing simple superphosphate, but fertilizer can be applied when digging the soil in a greenhouse at the rate of 100 g per 1 sq. m. The solution is prepared as follows: 20 g of superphosphate must be diluted in 3 liters of water, then diluted with 10 liters of water. Pour under the root, the norm is 30-50 ml per plant.
For indoor plants
Superphosphate can be used for indoor flowers, especially for flowering ones. With a deficiency of phosphorus, flowering will be poor, and the plant itself will look unhealthy, slowly increase in growth.
Before flowering in the spring, it is necessary to make a solution of superphosphate, potassium salt and ammonium nitrate. A 1 liter pot will require 70 ml of liquid fertilizer.
Top dressing is repeated 1-2 times a month until the onset of a dormant period. Slow growing plants and palms should be fed quarterly.
Extract from superphosphate
In order for phosphorus to be better and faster absorbed by plants, fertilizer must be applied not in dry form, but in the form of an aqueous solution. But here comes the problem. Phosphate fertilizers are poorly soluble in water. To get the hood, you need exposure to high temperatures.
Granular fertilizer must be poured with boiling water. For cooking, you need 300 g of superphosphate and 3 liters of water. The granules must be thoroughly mixed, although they will not completely dissolve, but will turn into a gruel.
Get a concentrate. It cannot be used in its pure form. To feed plants, dilute 100 ml of concentrate in 10 liters of water. You can add 0.5 l of ash solution and 20 g of nitrogenous fertilizer.
Foreword
In soils, the presence of phosphorus is often limited by nature to 1% of the total mass of macronutrients. However, this is not enough - the plants slowly enter the fruiting period, grow old faster, and take root poorly. The addition of superphosphate solves these problems.
How much phosphorus is in superphosphate?
The full formula of superphosphate looks long and confusing, because, in addition to the main component - phosphorus oxide, other macro- and microelements are also present in superphosphate. On average, phosphate fertilizers contain from 20 to 50% phosphorus. Not even more important percentage, and the water solubility of phosphorus oxide - thanks to this, the component easily reaches its goal, nourishing the roots, stems and leaves of plants.
The role of phosphorus compounds in plant life is incredibly important. Phosphorus stimulates the development of the root system, as a result of which plants more intensively receive everything from the soil. necessary components, slows down the aging process, improves the taste of vegetables and berries.
Today, the following types of phosphorus-containing fertilizers are available to farmers and ordinary gardeners:
- Monophosphate is the simplest fertilizer in the form of a gray powder. It contains about 20% phosphorus oxide, which explains the cheapness of such top dressing. In addition to phosphorus, there is up to 8% nitrogen, up to 10% sulfur. The rest of the volume is occupied by calcium sulfate or, simply speaking, gypsum.
- Granular superphosphate is a more complex and rich version of monophosphate. Granules are obtained by moistening the fertilizer and rolling industrial way. In this type of top dressing, the percentage of phosphorus oxide can reach 50%, in addition, the composition is improved with calcium sulfate. Granulated superphosphate for fertilizing cruciferous crops is especially valued. The use of granules allows you to stretch the effect of soil fertilization for several months in advance, since the granules dissolve rather slowly.
- Double superphosphate - as the name implies, contains a double portion of easily digestible phosphorus. There are few excipients in this composition, which makes it cost-effective for large agricultural companies. Double superphosphate contains up to 20% nitrogen, about 6% sulfur.
There are also ammoniated, magnified phosphates, with a high content of boron and molybdenum - their use is due to the specifics of the soil and the preferences of the crops grown.
Watching plants - signs of shortage
Thus, you can safely lay double superphosphate in the wells for perennials, shrubs and trees. It will be useful for beginners to know the signs of the need for the use of phosphate fertilizers. The plants themselves will tell you everything, you just need to observe - if the green mass acquires dark shade, foliage with reverse side or even from the front it becomes bluish, with a rusty tint, then all signs of a lack of phosphorus are evident.
Bluish shades in the color of the leaves can often be observed in early plants and seedlings undergoing hardening. This is normal - at low temperatures, the roots do not perceive phosphorus well, and with warming the situation should improve. However, it doesn’t hurt to play it safe - add double superphosphate with watering.
Phosphorus-containing fertilizers are especially effective on alkaline and neutral soils. But too acidic soils react with phosphorus oxide, converting it into aluminum and iron phosphates, which are practically not absorbed by plants. This problem can be solved with the help of preliminary application to the garden or slaked lime. These components are evenly scattered over the site at the rate of 200 grams of ash or 500 grams of lime per square meter and dug up. You need to do this in advance so that the reaction has time to pass.
How to fertilize - mandatory rules
Monophosphate can be applied to the soil as in early spring and in late autumn. In both cases, the application rates are the same: one square meter- 40-50 grams with continuous application. It is best to use a seed drill to spread the fertilizer. The dose on depleted soils can be doubled.
When planting fruit trees in the hole, you can fill up all 500-600 g of superphosphate. Repeated use of phosphorus-containing top dressing will be needed no earlier than after 3-4 years - in this case, up to 70 g of macronutrients are added to the tree trunk. Simple superphosphate goes well with nitrogen fertilizers, and double superphosphate with potash fertilizers. What can not be done is to mix phosphate components with chalk, urea and ammonium nitrate. First, saltpeter or urea is added, and not earlier than a week later - phosphorus.
Since phosphorus and phosphorus-containing fertilizers are difficult to dissolve in water, gardeners sometimes apply them already in liquid form - this way they quickly reach the roots. How to transfer this substance from solid to liquid state? Everything is quite simple - you only need heat! To do this, phosphate fertilizers are poured with boiling water - the top dressing does not lose its beneficial properties, but it acquires a form that is convenient for making.
The container with the solution is placed in a warm place and stirred from time to time. The granules dissolve completely, or rather, are crushed to microscopic particles, per day, and the liquid takes on the appearance of a fatty cow's milk. In order not to miscalculate, dilute no more than 20 tablespoons of granular fertilizer per 3 liters of water. The finished suspension is also dissolved in water to obtain an already basic solution - 150 ml of superphosphate suspension is enough for 10 liters of liquid. You can also add 20 mg prepared in advance a solution of wood ash - about 0.5 liters. Why nitrogen? In combination with it, phosphorus is better absorbed by plants.
Potatoes and tomatoes are lovers of phosphorus
It is these two crops that will be especially grateful for phosphorus top dressing. Everything is clear with potatoes - phosphorus acts primarily on root system, and in the case of potatoes, this affects the quality and size of the tubers. Most often, this fertilizer (double superphosphate) is applied in the spring, in each hole. It is best to use granular top dressing, it is easier to dose the amount of chemicals - about 4 grams are needed per bush.
If fertilizer is applied by surface dispersion, then in this case up to 20 grams of superphosphate are taken per 1 m 2. Such a dose of phosphorus will be acceptable for all vegetable crops.
Tomatoes, on the other hand, respond to the application of phosphate fertilizers with especially tasty fruits. In particular, tomatoes love potassium superphosphate. Phosphorus top dressing is applied to the soil during planting seedlings - in each hole up to 20 g. It is not necessary to bury the fertilizer deeply, it should be at the level of the root system. Almost all phosphorus is used by tomatoes to form fruits, so there is a practice of re-fertilizing during the flowering period.
It should be noted that young plants with a weak root system do not absorb phosphorus well, therefore, in order to save money, long-lasting granular superphosphate should be used. But adult plants can also be fed with a suspension, the preparation method of which was described above.
Even supporters exclusively organic farming understand that without phosphorus it is impossible to grow good harvest tomatoes. Unfortunately, the natural saturation of the soil with phosphorus is very low, therefore, the use of phosphorus fertilizers is necessary for growing vegetable crops. Superphosphate - complex mineral mixture, containing nitrogen-phosphorus compounds, the most important trace elements and minerals, is ideal for feeding tomatoes, since phosphorus oxide is present in this fertilizer in an accessible and easily digestible form.
The use of superphosphate for feeding not only tomatoes, but also other vegetable, fruit and berry crops convenient because the drug has a long aftereffect. It can be applied to the soil in large quantities without worrying about overdosing, as plants consume exactly as much phosphorus as they need. Experienced growers know how to count right amount and the duration of the fertilizer, so they achieve high yield any vegetable crop.
With a sufficient content of phosphorus in the soil, plants develop better and faster, their vegetation period is extended, the quality and taste of fruits improve. And with a deficiency of this element, there is a lag in growth, which, of course, affects fruiting. The following points indicate that the time has come to apply superphosphate for feeding tomatoes. external signs on plants:
- noticeable darkening of the leaf plates - the leaves become dark green with a bluish tinge;
- rusty spots appear on the stems and leaves;
- the underside of the leaf may acquire a purple color.
Most often, such signs appear on tomato seedlings that have been hardened off, or after a sudden cold snap. At low temperatures, the absorption of phosphorus by the roots is difficult, but with an increase in temperature, the color of the leaves, as a rule, is restored. If this does not happen, then the plants must be additionally fed with superphosphate. 
The drug is usually applied to the soil in the spring before planting or in the fall. Autumn application is more preferable for fruit crops, because the mixture supports the root system and facilitates the wintering of the plant. For tomatoes, superphosphate is best applied in the spring when digging the soil. But you can also pour fertilizer directly into the hole when planting seedlings at the rate of 1 teaspoon / 1 plant.
Video “How to fertilize”
From the video you will learn how and when to fertilize tomatoes.
What soils to use
Phosphorus in the composition of the fertilizer is in a form in which superphosphate can be used for any soil. It always remains available to plants, and they can absorb it in the required amount. The most effective fertilizer manifests itself on fertile soils with a neutral or alkaline reaction. But on acidic soils, its absorption by plants is a little difficult. 
With an acid reaction, the absorption of phosphorus by the roots slows down, therefore, before applying the preparation, the acidity of the soil must first be leveled with ash (200 g / 1 m² of area) or lime (0.5 kg / m²). After leveling the acidity, superphosphate is applied no earlier than 1 month later. Otherwise, the fertilizer efficiency will be significantly reduced.
In acidic soil, the action of superphosphate can have unpredictable consequences. This is especially true for inexpensive mixtures, for the manufacture of which manufacturers use non-pure raw materials.
In any other soil, nothing bad will happen, but in an acidic environment, such a fertilizer can turn into iron phosphate, which makes it unavailable to plants. Therefore, with a noticeable deficiency of phosphorus in the soil, it is still better to use more expensive preparations. But if you are sure that the acidity of your soil is not increased, then any kind of superphosphate can be used.
Instructions for use
Superphosphate is applied directly to the soil in spring period or at the end of the season. Consumption rates of fertilizer for soil are 40-50 g / 1 m² of area for fertile lands and 50-70 g for soils that have long been used in crop rotation. The total amount of fertilizer for depleted soils should be increased by about 30%. Such an expense is acceptable for the areas where seedlings are grown, vegetable crops, greens, cereals and other types of agricultural plants. For growing crops in greenhouses, the norms of superphosphate increase to 80-100 g / 1 m² of soil. 
For feeding fruit trees and berry bushes, 40-60 g of fertilizer / 1 plant is used, depending on its age and size. When planting seedlings, up to 300-500 g / 1 planting hole can be applied once. If fed mature tree or a bush, then the granules are embedded in the near-stem circle before flowering. But it is also permissible to dissolve the indicated amount of the drug in water and use it for irrigation, but you should be aware that the dissolution of superphosphate does not occur quickly.
For nightshade crops: potatoes, eggplants, tomatoes, it is better to apply superphosphate in granular form directly into the hole during planting. With continuous application to the soil during digging, the preparation is scattered in the amount of 20-30 g / 1 m² of planting area. When using superphosphate in gardening, you need to know that it is not compatible with other nitrogen fertilizers (mixtures), as well as with chalk (lime).
Types of superphosphates
For ease of use, superphosphate is available in several forms and varieties:
Do not disregard another "folk" type of phosphorus top dressing - an extract from superphosphate. Since phosphorus is poorly soluble in water and this slows down its absorption by plants, gardeners have come up with a method that turns superphosphate into liquid fertilizer and how to apply it to tomatoes. To completely dissolve the granules or powder, they are poured with boiling water. This saves all beneficial features substances, but it passes into an easily digestible aggregate form.
Preparation of funds takes a whole day. At this time, the dishes with the solution are placed in a warm place and periodically stirred so that the drug dissolves better. The finished suspension should look like high-fat milk. 
Next, the extract must be diluted with water, first in a proportion of 20 tbsp. tablespoons / 3 l of water (a working solution is obtained, from which the top dressing itself is prepared later), and then prepare the main top dressing: add 150 ml of working solution, 20 g of nitrogen, 0.5 l of ash to 10 l of water. Nitrogen in the composition of top dressing is required - without it, phosphorus will not be absorbed. The hood is used for root application by irrigation.
Application for tomato
Superphosphate is universal fertilizer, but it shows the highest efficiency when applied under horticultural crops: potatoes, eggplant, tomatoes. Tomatoes are especially responsive to this top dressing: the bushes become more powerful, and the fruits are sweeter and not watery. When applying superphosphate for tomatoes, you should adhere to the norm of 20 g / 1 plant (bush). 
As a rule, the drug is applied in a dry, better granular form. The powder is evenly distributed in top layer soil. It is not necessary to deepen the granules strongly. Optimal depth embedding - at the level of the location of the roots. More than 90% of phosphorus is used by tomatoes for the formation and ripening of fruits, so the application of superphosphate should not be limited to spring top dressing, but should be continued until the end of the flowering period.
Superphosphate is a mineral fertilizer formed during the breakdown of natural phosphates. The main component of the fertilizer is phosphorus, necessary for the proper development of cultivated seedlings. Gardeners always use phosphorus top dressing for a stable crop and tasty fruits. Consider how to use superphosphate in the garden, how to properly prepare it for fertilizer, how to do it. We will also consider the optimal proportions for feeding the fertile layer of the earth.
Features of the drug
Phosphorus preparations are obtained from natural material formed in the earth layer during the decomposition of the bones of biological organisms and iron ores. It is impossible to find phosphorus in its pure form, but it is sometimes present in other mineral compositions and organic compounds in the form of oxides. There is also not enough phosphorus in the fertile soil layer, so it must be added when growing plants.
Among the variety of agricultural fertilizers that are sold in gardening stores, you can see various combinations of phosphates with other micronutrients. Among them, superphosphate is in great demand.
The formula of simple superphosphate is: (CaH2PO4) 2 x H2O + 2CaSO4 x 2H2O.
The phosphorus substance in a simple agricultural preparation contains at least 20%, in complex compositions of superphosphates it contains about 50%.
The benefits of phosphorus for seedlings:
- activates the growth processes of green mass and roots with bulbs;
- makes fruits sweeter and tastier;
- removes nitrate compounds from foliage and fruits;
- prolongs the growing season;
- prolongs fruiting and flowering;
- nourishes seedlings with an important substance for development;
- restores disturbed metabolic processes in tissues;
- strengthens immune system green shoots;
- stops the oxidation of the fertile layer;
- contributes to better keeping quality of the crop.
Gardeners say that even exceeding the rate of applying phosphorus oxide to the ground will not harm the seedlings: they consume the most optimal percentage from the soil. But the deficiency of the trace element will immediately affect the growth and external defects of plants:
- leaves acquire an unnaturally concentrated color;
- "rust" appears on the leaves;
- sometimes the leaves may turn blue;
- a purple tint may appear on the back of the leaf.
If a change in the color of the green mass is detected, apply a phosphorus fertilizer.
Varieties of superphosphates:
- simple;
- double;
- in granules;
- powdery.
Simple
This agricultural product is a combination of phosphates, sulfur, calcium and magnesium. It is produced in granulated form or powder, soluble in water. This agrochemical is designed to feed the soil of any structure. Simple superphosphate is especially useful for seedlings that need a sulfur component. However, other garden plantings also respond well to it.
Note! Simple superphosphate is used for emergency feeding of green spaces during the growing season.
The addition of superphosphate to autumn time and at spring work enriches the earth with a mineral complex useful for garden plantings. Superphosphate is buried in the fertile layer to the depth of a shovel: granules or powder. The granulated product is scattered when planting seedlings in pits and when sowing seeds: they make shallow grooves and cover them with earth along with the seeds. Also, the granules are placed in the planting holes along with the seedlings.
Double superphosphate
This type of phosphate is a concentrated substance for feeding the soil. The product contains the same trace elements as simple phosphate. Granules and powder are well diluted with water, only their concentration is different. This fertilizer is also used on the soil of any texture. The drug is used to enrich the fertile layer during spring / autumn work ah in the garden to the depth of the shovel. It is also used during planting work: holes and grooves are filled with powder / granules.
Double superphosphate is consumed less than simple.
Double superphosphate is also used for emergency feeding of seedlings if they are deficient in this trace element. Make an aqueous solution and irrigate the beds. Since the agrochemical has a high nitrogen concentration (15%), crops should not be fed before harvesting fruits and when preparing bushes / trees for wintering. Nitrogen activates landscaping, which is undesirable before the onset of cold weather.
Powder
The agro-mixture in powder form is characterized by flowability, it is stored for a long time, and does not stick together. However, it is necessary to observe the permissible concentration of dampness in the room according to the instructions. In powder form is up to 20% phosphorus oxide. Accordingly, the agricultural product is not expensive. The powder is more efficient to bury directly into the ground.
Granules
This agricultural product is more comfortable to use, but it costs more than powder. It has a higher concentration of phosphorus - up to 50%. The formula of the preparation with granules is Ca(H2PO4)2-H2O + H3PO4+2 CaS04. Granules dissolve worse in water: they are either poured onto the ground or used for compost.
There are also other types of superphosphates: boric, magnesian, ammoniated, etc. They contain additional trace elements that combine well with phosphates.
Incompatible connection
This type of mineral additives is not combined with alkaline and other components: lime, chalk, carbonate and ammonium nitrate.
Dosage of the drug
The correct proportion of phosphates in the soil ensures quality development horticultural crops. The dosage must be calculated from the needs of the agricultural crop and the characteristics of the soil structure. For soils depleted in microelements, the concentration of the agricultural product increased by 30% is used.
- Leafy and vegetables: 30-40 g of double superphosphate per square meter or 60-80 g of simple superphosphate.
- Fruit trees (planting) - up to 600 g of double or 1 kg of simple superphosphate under one tree.
- Feeding tree seedlings - 70 g per plant.
- For planting potatoes, take 4 g of a double or 8 g of a simple agricultural product.
- When digging the site, the dosage is 40-70 g per square meter.
- For potatoes - 20 g per square meter when preparing the soil for planting.
In greenhouse plantations, 80-100 g per square meter is used. Phosphates are applied in combination with potassium preparations and nitrogen compounds.
Note! Sometimes the granules / powder are not covered with earth, but simply laid out on the surface.
Top dressing of tomatoes
First feed the young seedlings. An aqueous mixture of superphosphate is prepared and liquid ammonium nitrate is poured into it. Saltpeter helps young shoots to better absorb phosphorus.
When landing on a garden bed, for each hole, a nutrient mixture is made from ash (half a handful), humus (a handful) and superphosphate (a pinch). This mixture is placed on the bottom of the landing hole, and sprinkled on top. fertile soil. This is necessary so that the roots do not come into direct contact with the fertilizer.
When the tomatoes begin to bloom, they must be sprayed. To do this, prepare an aqueous solution based on 50 g of powder / bucket of water. During fruit set, a different composition is used: 2 tablespoons of powder are diluted in a bucket of water, and then (2 dessert spoons) and half a liter of liquid chicken are added. One sapling takes a liter of nutrient mixture.
If the fertile layer in the garden is different hyperacidity, before using phosphates, it must be alkalized with ash or lime. On m2 of landing area, take 200 g of wood ash or half a kilogram of lime. 30 days after the alkalization of the fertile layer, phosphorus top dressing can be applied. If this is done earlier, then the drug will lose most of the nutritional properties.
Top dressing of cucumbers
Greenhouse crops begin to fertilize from the beginning of spring. In the fertile layer contribute 20 g per running meter the following drugs:
- ammonium nitrate;
- superphosphate;
- potassium sulfate.
After the formation of four leaves, the cucumbers are fed as follows. In a bucket of water, dilute 20-25 g of double superphosphate and 22 g of potassium sulfate. One plant takes a liter of the finished mixture.
As soon as the cucumbers bloom, they are irrigated with the following solution: 35-30 g of superphosphate is diluted in a bucket.
If the leaves begin to turn yellow, the cucumbers are fed with the following solution: 10 g of ammonium nitrate, superphosphate and potassium salts are dissolved in a bucket. When irrigating, try not to get on the leaves, as the solution can burn them.
Top dressing of garlic
Before planting garlic, you need to prepare the soil. To do this, it is well dug up and 20 g of superphosphate (double) is added for each square meter. Together with it, half a kilogram of dry ash and 30-25 g of potassium sulfate are added. Nitrogen compounds when planting garlic will only harm, as juicy greens will appear instead of the head.
Houseplants
For ornamental seedlings, ammonium superphosphate is used. It is added to the soil mixture when planting flowers in a flowerpot - 1% granules for 60% soil for double superphosphate and 1% powder for 30% soil for simple. When watering, the following proportion is used: 30 g of an agrochemical is diluted in a bucket of water (take double) or 60 g of a simple powder.
When the plant begins to gain green mass and goes into active growth, you need to make a mixture for irrigation - a teaspoon of superphosphate on a bucket of water. When flowers appear, the dosage of fertilizer is increased by 2.5 times.
Preparation of working solution
Gardeners know that phosphates do not dissolve well in water, so they need a special approach. In order for the powder to dissolve without residue in water, it must be heated to a boiling state. It is in boiling water that the powder dissolves well and becomes suitable for use. You should not worry that the powder will lose its beneficial substances: it will simply become easily soluble.
The mixture is placed in a warm place and periodically stirred with a wooden stick. After 24 hours, the powder will completely dissolve. Appearance mixture resembles rustic full fat milk. The mixture is poured into another container, and the undissolved precipitate is again poured with boiling water for 6-8 hours (also 4 liters).
The working solution is prepared from 2 kg of the drug per 4 liters of boiling water. Another 4 liters of secondary solution are added to it, and then another 2 liters. Next, 500 g of diluted ash and 22 g of nitrogen fertilizer are added to the bucket.
Note! Gardeners advise combining nitrogen fertilization with phosphorus oxide: without it, phosphorus substances are difficult to absorb by seedlings.
The tandem of phosphorus with nitrogen is especially important for spring top dressing, since garden plantings need a large amount of nitrogenous compounds. It is nitrogen that contributes to greening, and phosphorus - the formation of tubers and roots.
Preparation of granules
To dissolve the granules in water, use the following proportions. Three liters of boiling water pour 20 tablespoons of the substance. The mixture is best prepared in a large container such as a tank or barrel. When the granules dissolve, 10 liters of ash solution and 400 g of carbonate are added to the barrel.
Compost
In order for phosphorus oxide to be well absorbed by the root system, gardeners recommend making compost. For this, when forming compost pit agrochemical granules are added. For 10 kg of organic ingredients, 10 g of superphosphate is consumed: they are sprinkled with layers of a compost heap.
For compost, simple superphosphate is used, not double.
After maturation of the compost, excellent humus is obtained, enriched with phosphorus compounds readily available to plants. However, you should not think that superphosphate helps the compost ripen faster: you just get humus with the addition of phosphorus at the exit.
Bio extract
Phosphorus, which is well absorbed by plants, can be prepared using a humate solution. To do this, superphosphate powder (2 tbsp / l) is diluted in liquid potassium humate (1 tbsp / l), adding warm clean water(bucket). The mixture must be stirred periodically, and in a day it will be ready. Humates are obtained by the natural decomposition of organic matter. They are very useful for green spaces and accelerate their natural development. Humates provide better assimilation of phosphorus by cultures.
You can also buy humated superphosphate in stores, it is already enriched with humic acids. An important feature humates is to reduce the concentration of nitrates in the fruits and greenery of plants.
Superphosphate substitute
What can replace the agrochemical with garden plot? The people have long been used for these purposes from cattle or fish. However, you need to know that in bone meal, phosphorus is in a hard-to-reach form and is more slowly absorbed by plants. Therefore, it is necessary to alternate the application of an agrochemical with organic phosphorus fertilizers.
The difference between bone meal and superphosphate is in organic origin.
Bone meal contains not only phosphorus, but also calcium. Also in this organic matter there are many other trace elements. When buying fertilizer, you should give preference to defatted powder, as it contains more phosphorus.
Since bone meal decomposes slowly in the ground, one dose of application is enough for the entire growing season. Minerals will gradually enter the tissues of plants, nourishing them with phosphorus. Unlike mineral preparations, organic powders do not burn the roots and leaves of plants.
Bone meal can be fed to plants at any time and in any weather. If you add it shortly before harvesting, the taste of the fruit will improve much. just before fertilizer acidic soils must be limed, as excessive acidity neutralizes the benefits of phosphorus.
To fertilize the planting area with bone meal, you need to add 200 g of dry matter per square meter and dig it up well. If you need to feed the seedling, then before planting, pour 15-20 g of flour into the hole.
Flour is also used in dissolved form. To do this, dissolve 100 g of the substance in two liters of boiling water or very hot water. The mixture must be constantly stirred for 7-8 days so that the dry matter is completely dissolved. After that, you need to filter the solution and dilute it in four buckets of clean water. The solution is irrigated with any green plantings in the garden. If they feed the vegetables and fruit trees a couple of weeks before harvest, the taste of the fruit will be just great.
Outcome
Despite the availability of innovative agrochemicals, simple superphosphate continues to be in great demand among summer residents and gardeners. They fertilize seedlings throughout the vegetative period from early spring to autumn work. However, one should distinguish between simple superphosphate and double: the latter contains more nitrogenous substances. Nitrogen should not be added to the soil during fruit ripening and when preparing plants for wintering, because it activates the rapid growth of stems and leaves. In autumn and late summer, simple phosphorus powder is used for top dressing.
Superphosphate is used both in pure form and in liquid solution. To qualitatively dissolve the powder and granules in water, they are poured with boiling water. It is also useful to combine superphosphate with humates: they stimulate the rapid development of seedlings and facilitate the absorption of phosphorus by the root system. Compost with the addition of superphosphate is also popular: the output is an organic substrate enriched with phosphorus.
