Almost every gardener or gardener knows what superphosphate is. Fertilizer (its use is widespread almost everywhere) is a substance that contains about twenty-six percent of phosphorus soluble in water. In addition, simple superphosphate contains magnesium (less than a percent), about 17% calcium, 10% sulfur, and about six percent nitrogen. Part of the phosphorus in the fertilizer is free phosphoric acid (about 2.5%). The proportion of water in a substance is equal to two percent. The predominant granule size in a quality material should be about six millimeters, inclusions of 1-4 mm are allowed.
In what other form does superphosphate exist? Fertilizer, the use of both varieties of which can significantly improve the yield, is also produced in the form of double superphosphate. It differs from the ordinary production process. The double variety is extracted from natural phosphates through electric sublimation and further oxidation of phosphorus (H 3 PO 4 is formed ), while ordinary grades are obtained by acid decomposition.
What else distinguishes between double and ordinary superphosphate (fertilizer)? The use of the double option on low-fertile soils gives positive results, since it contains up to 86% of useful substances, including easily absorbable phosphates - 52%, potassium - 34%, a small amount of chlorine and other substances. In its appearance, this superphosphate is a substance of various shades of gray that must be stored in closed warehouses with protection from access to rainfall and groundwater, because it absorbs water well. For users, the material is non-toxic, in addition, it does not burn and is explosion-proof.
How is superphosphate (fertilizer) used? The general plan instruction recommends that you first study the composition of the soil on the land. If its reaction is neutral or alkaline, then the benefits of using these substances will be maximum. In the case of acidic soils, this fertilizer must be mixed with limestone or humus in order to prevent the conversion of superphosphate into indigestible aluminum or iron phosphate.
When should superphosphate (fertilizer) be added? Its use is allowed when sowing seeds of cucumber, corn, tomatoes, beets, etc. into the wells. In addition, from 40 to 60 grams of fertilizer per square meter can be applied. meter for bait garden trees, from 15 to 20 grams per square. meter for fertilizing plants in dry form and up to 50 grams per square meter. meter when digging a land plot for the winter.
Superphosphate is a fertilizer, the price of which today is about 15,000 rubles per ton. It allows you to increase yield, improve the taste of fruits, positively affect the reduction of oxidative processes in plants, strengthen the root system. Its lack, for example, in potatoes contributes to the formation of rust spots in tubers, in tomatoes - it leads to small fruits and spotty leaves. Red currant reacts to a lack of fertilizer with increased acidity of berries, but raspberries do not develop shoots.