Mineral fertilizers are the basis of modern agriculture. They can significantly increase the fertility of even very poor soils, which makes it possible to grow rich crops in almost all regions of the country. Given that the characteristics of soils in most of our regions are far from perfect, this is a very valuable property.
Of course, their choice should be approached with all possible responsibility, since the introduction of excessive amounts of mineral fertilizers into the ground may well lead not only to the death of plants, but also to poisoning people with nitrates and nitrites. One of the most effective agents of this kind is double superphosphate.
When is it necessary to apply?
Imagine that you have a beautifully maintained garden. One day you may notice that the condition of the leaves on the plants leaves much to be desired: the lower part of the leaf blade acquires an unnatural green-violet hue, and the yield drops sharply ... These signs indicate that you urgently need double superphosphate.
In addition, falling off the ovaries, which are extremely sensitive to the lack of many trace elements, is also a fairly reliable sign.
What is phosphorus for?
Note that absolutely all plants on our planet need this substance. The problem is that in soils the content of available phosphorus compounds rarely exceeds 1%, and in most regions this value is even less.
Especially young, intensively growing seedlings need phosphorus, since this element ensures the flow of energy processes in cells and tissues. And plants do not know how to get it from somewhere other than from the ground. Fortunately, today in stores there are a huge number of various kinds of fertilizers, one of which is just double superphosphate.
What does it contain?
So, you have come to the store. Remember that there are many types of superphosphate, but you need exactly double superphosphate. Its formula is Ca (H 2 PO 4 ) 2 * H 2 O.
It includes at least 50% (+ -5%) of phosphorus. Moreover, it is in an easily digestible form for all plants. In addition, it contains 15% (+ -2%) of nitrogenous compounds, which can also be actively absorbed by plants. Do not forget about sulfur (6%). Unlike simple superphosphate, it lacks gypsum. This means that using it for deoxidation of soils will not work.
This fertilizer is available in the form of granules, it is highly soluble in water. It is very important to bring it into the ground in early spring or autumn (after harvesting). Otherwise, phosphorus simply will not have time to distribute in the ground. In addition, we would recommend that all plants (at least two times per season) that lack phosphorus are watered with a superphosphate solution. Like many other mineral fertilizers, it can be used on any soil.
How to dose it?
Unlike many products, double superphosphate fertilizer does not need to be applied strictly for digging the soil: you just need to sprinkle the granules on its surface in the dose indicated on the factory packaging. However, its dosage largely depends not only on the type of cultivated plant, but also on the characteristics of the soil itself.
So, agronomists recommend applying from 30 to 40 g per square meter of soil if you plan to plant vegetables or greens on this site. In the case when your garden is located on a site with poor soils, the amount of fertilizer should be increased by approximately 20-30%. If you want to improve the taste of fruits, then under one fruit tree, you need to pour about 500-600 g in the fall. This is most conveniently done when digging trunks circles. About 90-100 g are poured into greenhouses and greenhouses, and when planting potatoes and other nightshade crops, 3-4 g are put into a hole.
Attention! In no case do not exceed the recommended dose, as in this case, burns of plant roots are possible. Mineral fertilizers are quite chemically aggressive substances, so you should not forget about this in any case.
Other recommendations for use
As we have already said, double superphosphate is perfect for use on any type of soil and for any agricultural plants. It is important to remember that a greatly reduced soil pH reaction may interfere with its dissolution, and therefore acidity must be reduced before application. To do this, when digging, make 200 g of ash. In addition, you can use 500 grams of ordinary lime per square meter of area.
Remember! Double granular superphosphate should be added only a month after deoxidation, otherwise it will lose almost all of its useful properties. As we already said, it can be used not only for digging, but also scattered with a thin layer on the surface of the soil, or added to each well.
The proportion should be looked at on the package, since for different types of plants it can seriously differ. It should not be mixed with lime, urea or chalk in any case, since due to the ongoing chemical reaction, the fertilizer becomes almost completely useless.
In addition, in this case, compounds may turn out that will not affect the condition of your plants too positively, so it is better not to experiment.
What do they get it from?
Like other types of mineral fertilizers, double granular superphosphate (the use of which we have examined) is obtained from the bones of domestic animals, as well as from certain types of minerals. In other natural formations, there is simply not enough digestible phosphorus. Thus, the words of Academician Fersman about phosphorus as a “biogenic mechanism of life and thought” are fully confirmed.
By the way, how much does this fertilizer cost? In most agricultural stores, its price does not exceed 100 rubles per kilogram. Of course, when buying it in bulk, the price will be slightly lower, so the owners of large gardens should remember this.