In the instructions for growing any culture, whether it be a vegetable, fruit or flower, nutrition is always present. Many gardeners, mistakenly believing that only organic fertilizers are beneficial to plants, carefully harvest tons of compost and manure. But plants also need minerals.
Practice shows that excellent results are obtained if timely fertilizing with superphosphate of all vegetable crops, fruit trees, berries, ornamental shrubs and flowers is carried out. It is not necessary to think that in this preparation one “chemistry” is harmful to health. Superphosphate is a complex compound, which contains many substances that plants need to build green mass and bear fruit.
Basic information
Superphosphate belongs to the category of simple mineral phosphorus fertilizers. This preparation is a gray powder which, during storage, has very little caking and has medium dispersibility. Its formula is: Ca (H 2 PO 4 ) 2 * H 2 O and CaSO 4 .
In this substance, perfectly assimilated by plants, P 2 O 5 contains up to 19.5%.
From the name it is clear that the main chemical element in superphosphate is phosphorus. It is present in two forms - phosphoric acid and monocalcium phosphate salt. These two components can be from 20% to 50%, which is indicated on the factory packaging. Superphosphate fertilizer also includes:
- Gypsum.
- Silica.
- Iron phosphate
- Fluorine compounds.
- Aluminum phosphate.
Consider the role of each ingredient in plant life.
Phosphorus
The raw materials for this element are phosphorites, which are sedimentary rocks. Phosphorus is essential for plants. They signal that it is not enough by changing the color of their foliage from green to bronze, purple, purple. Phosphorus and its compounds help plants become more frost-resistant, easier to tolerate drought, accumulate starch, fats and sugars.
The introduction of superphosphate promotes earlier ripening of the fruit precisely thanks to the phosphorus contained in it. This element is a component of complex proteins that are involved in cell division. As a result, superphosphate fertilizer promotes the formation of new branches, buds, ovaries, leaves. Plants receiving such top dressing grow stronger, have a lush crown (trees), form more fruits.
Gypsum
You are mistaken if you believe that gypsum is used only in medicine for fractures of the limbs. This raw element is a very valuable fertilizer, as it is a rich source of calcium and sulfur. Its formula is CaSO 4 .
Plants need calcium to increase yields, regulate nitrogen intake, and most importantly, to increase immunity to various diseases.
If this element is not enough in the soil, small fruits are tied. Even before harvesting (being green) they crack. In flowers with a lack of calcium, the buds die off and fall off. In fruit crops, the apical buds of shoots dry out.
Fertilizing with superphosphate, which contains gypsum, helps to avoid all these phenomena, increase productivity, make flowering of ornamental crops more magnificent, and increase the shelf life of harvested fruits.
Silica and fluorine
Silica is silicon oxide (SiO 2 ). This element is necessary in the soil, because it improves the digestibility of phosphorus, as well as potassium, magnesium and other useful substances, affects the metabolic processes in plants, stimulates the development of the root system, thereby expanding the nutrition zone. Silicon makes plants more resistant to frost, drought, toxic poisoning, damage by pests. Scientists have found that the presence of silicon in the required volumes increases the yield of cereals, cucumbers, and potatoes. In tomatoes with a lack of silicon, the fruits either do not set or remain small.
Fertilizing with superphosphate containing silica significantly increases the yield of tomatoes and potatoes. The introduction of it during the cultivation of many other agricultural and ornamental crops is also beneficial.
Concerning the fluorine compounds present in superphosphate mainly in the form of sodium fluoride, there is no consensus. Some experts argue that fluorine compounds paired with phosphorus increase the yield of root crops. Others believe that this substance in small doses does not have a noticeable effect on plants, but in large doses it tends to accumulate in leaves and reduces yield.
Useful properties of superphosphate
From all the above, we can conclude that the use of superphosphate is advisable as a fertilizer. This drug has such effects on plants:
- Increases productivity.
- Makes them less susceptible to cold and drought.
- Helps withstand diseases and pests.
- Stimulates the growth of the aerial part.
- Extends the shelf life of fruits.
- Develops a root system.
- Improves the taste of fruits.
- Slows down the aging of plants.
Whether fertilizer is necessary or not, can be determined by the color of the leaf plate of the culture.
Superphosphate can be used in parallel with potash and nitrogen top dressing. You can not apply fertilizer with superphosphate in parallel with chalk, urea, ammonium nitrate.
Dual superphosphate
The formula for this substance is Ca (H 2 PO 4 ) 2 · H2O. In it, P 2 O 5 , perfectly assimilated by plants, is much larger than in simple superphosphate, namely from 45% to 48%.
Gypsum is also present in the composition of double superphosphate, but its percentage is lower. However, in this fertilizer there are additives of manganese (up to 2.5%), boron (up to 0.3%), ammonia (up to 1.6%), molybdenum (up to 0.1%). Each of these elements contributes to the properties of the drug.
Manganese is an integral part of many important proteins. It is necessary for plants for many redox reactions, in particular, for the conversion of nitrates to ammonia. Most of all, the lack of this element affects the berry, plum, apple, cherry.
Molybdenum is also necessary for all plants, although the need for it is slightly lower than in other chemical elements. This has been taken into account in the production of double superphosphate. The characteristic of mineral fertilizer reflects the percentage ratio of each component and shows that molybdenum in the preparation is the least (0.1%). But even in such quantities, this element has a beneficial effect on plants. It enhances photosynthesis, participates in the formation of chlorophyll, plays an important role in biochemical processes, in carbohydrate and phosphorus exchanges, and helps to convert nitrates to ammonia.
Boron is another very important chemical element. It increases productivity, promotes the accumulation of starch in potatoes, and sugar in sugar beets, improves seed quality, activates flowering and fertilization.
Ammonia is valuable in that there is a lot of nitrogen in it (up to 82%). As you know, nitrogen is required by plants, like people bread. Therefore, all of them very actively absorb nitrates, which tend to accumulate in fruits and leaves. Plants absorb ammonia into themselves without "appetite", but it plays the same role as nitrates, completely not accumulating either in leaves or in root crops, or in ovaries, or in fruits.
As can be seen from the above brief description, double superphosphate plays a very important role for plants during their growing season.
Granular Superphosphate
In addition to superphosphate, the powder industry produces this fertilizer in the form of granules. Some gardeners are surprised at the different price of such a chemical with an equal amount of it in the package. It depends on the granulation method. A wet preparation (performed using water and steam, but the fertilizer itself is dry to the touch) is always more expensive than pressed.
Granular superphosphate itself is a fertilizer that works much better in soil than powder, despite the fact that their chemical composition may be identical. This is another explanation why in granules, drugs are always more expensive.
Benefits:
- Lower consumption when used on an equal footing with powder superphosphate.
- It has a prolonged effect (it dissolves gradually, without losing its properties, plants take it as needed).
- It is possible to fertilize the soil over large areas mechanically (the wind does not carry the field).
- It is not washed by water.
Soils and application methods
In almost all types of soils, the use of superphosphate is advisable. Fertilizer should be applied with caution only in soils with a pH below 6. If the soil acidity is high, before adding phosphorus preparations to the plants, “fluff”, slaked lime, ground egg shells must be added, that is, the soil should be produced and thus bring its pH closer to neutral values.
There are several ways to apply superphosphate to help reduce chemical absorption in the soil:
- The use of granular superphosphate.
- Local application.
- Placing fertilizer in grooves made in the ground.
- Spot application.
- Fertilizing plants with a water extract from the drug.
In the latter version, the drug penetrates the root system faster and begins its work. It is not difficult to make a water extract. It is only necessary to pour granules with boiling water and mix thoroughly until they are completely dissolved. Recommended proportions for the working solution: 20 tablespoons of superphosphate and 3 liters of water. To fertilize plants, you need to take 150 ml of this solution in a bucket of water.
There is another way to make an aqueous solution of superphosphate. This requires composting the fertilizer with preparations containing live bacteria, for example, with humates. When the mixture is ready, it is diluted in water and incubated for 24 hours for final ripening. After that, it can still be diluted with water and used to fertilize any crops.
Feeding Times
Superphosphate is an ideal choice for spring garden applications. It is used as root dressing, which provides plants with active growth, an increase in green mass, and good development. In general, all this helps them to resist diseases and pests, accumulate useful substances in their parts, and delight with lush flowering and fruit setting.
On average, simple superphosphate is added per square meter from 40 to 50 grams, and double and granular from 20 to 30 grams. Note that in a standard tablespoon of the powder preparation is 18 grams (without a high slide), and granular - about 16 grams. For trees, the rules are different. If their age is older than 3 years, under each you need to make up to 600 grams. It is most convenient to make holes with a metal or wooden peg around the trunk with a depth of about 50 cm, place fertilizers in them, and fill up with earth after the hole. The roots themselves will take fertilizing as much as they need.
In the summer, some crops are given foliar top dressing by extracting from superphosphate.
If the plants are overfed with this fertilizer, their roots can be burned, thereby causing not active growth, but a disease and developmental delay. Symptoms of an overdose may be brown spots along the edges of the leaves, brittle stems.
Many gardeners practice superphosphate fertilizer in the fall, when digging a garden or field. With this application, the drug manages to "disperse" on the soil, which will help the plants immediately start using it in the spring.
Instructions for use for some plants
When planting potatoes, it is better to use granular fertilizer, placing it 3-4 grams in each well.
Instructions for the use of superphosphate fertilizer for tomatoes say that it must be applied when planting seedlings of about 20 grams per bush. It is better to pour the fertilizer not into the hole, but into the grooves made in the ground next to it. So you can protect the roots from burns. Another way is to uniformly apply superphosphate in the autumn to the garden where it is planned to plant tomatoes in the spring.
For tomatoes, it is useful to top dress with superphosphate during the flowering period. Dosage in this case: a teaspoon of granules per 10 liters of water. This drug is for root dressing. If you make a solution for spraying the leaves, then you need to dilute 10 ml of superphosphate extract in 10 liters of water.
For cucumbers, it is useful to use this drug several times. In autumn, it is introduced into the soil when digging the beds. Standards: from 20 to 30 grams per square meter. With mass flowering, root dressing is done, contributing 20 grams per square meter. In the process of fruit ripening, if the soil is poor, cucumbers are fed again by spraying them with an extract of superphosphate diluted in water. Norms: 10 ml per bucket.
The instructions for the use of superphosphate for garlic say that this culture is fed twice with phosphorus preparations.
The first time is in the fall, when humus, superphosphate and wood ash are added to the bed about 10-15 days before planting. The second top dressing (spring) is carried out using urea. Therefore, superphosphate is not added. It is used for the third top dressing, when garlic begins to form and grow heads. Standards: 2 tablespoons of granular fertilizer per bucket of water. About 5 liters of such a solution should be consumed per square meter.
It is recommended to feed berries and trees with superphosphate in the fall, so that they can more easily withstand the winter cold. It’s best to add fertilizer to each bush. Norm: 2 tbsp. spoons that need to be evenly distributed in the trunk circle, buried in the ground by 10 cm.
If we are talking about currants and raspberries, then it is advisable to add humus and potassium salt to superphosphate.
For apples and pears, it is very useful in autumn to apply double superphosphate at 30 grams per square meter of area around the tree. If plums and cherries are fertilized annually in this way, then once every five years it is necessary to check the soil for acidity, and in the case of very low pH values, lime the soil in near-stem circles.