One of the most convenient and useful fertilizers for use in the garden is superphosphate. This is a drug belonging to the group of phosphorus supplements. Phosphorus is one of the main components that plants need for normal development. In the absence of this element, the development of plants is inhibited, the fruits grow small. Superphosphate eliminates this problem, but an overdose of fertilizer does not benefit the crop either.
Varieties
Superphosphate with a minimal set of chemical elements is often called monophosphate. This type is available in two forms: powder and granular. The composition of simple superphosphate:
- phosphorus 10-20%;
- nitrogen ≈8%;
- sulfur not more than 10%.
Monophosphate is a gray powder or granules.
In addition, there are also double superphosphate and ammoniated superphosphate. Double differs from simple in that ballast is removed from it, and the fertilizer itself contains twice the amount of phosphorus.
The ammoniated has a high sulfur content: up to 12%. The amount of gypsum (ballast) can reach up to 55% against 40-45% in monophosphate. Ammonized superphosphate as a fertilizer is used for crops that need sulfur. These crops include cruciferous and oil plants:
- cabbage;
- radish;
- radish;
- sunflower.
In addition to the ammoniated version, there are varieties of this fertilizer with other additives necessary for plants. The use of each of the varieties is justified by the existing specific problems. It is not necessary to pour fertilizers just like that “because there is another element there”.
How to use
The properties of superphosphate make it possible to saturate the soil with phosphorus for several years to come, thanks to the filler ballast. Gypsum is poorly soluble in water, so the trace elements that saturate it enter the soil slowly. The use of granular superphosphate as a fertilizer also makes it possible to “lighten” dense clay soil. Porous granules consist of compressed gypsum. Useful trace elements are gradually washed out of them during irrigation, and the granules themselves act as a soil baking powder. If it were not for the high consumption of fertilizer for top dressing, the use of simple superphosphate would in certain cases be more beneficial than the use of double superphosphate. But a simple feeding option is very inexpensive, which is why even now gardeners often prefer to use monophosphate.
On packages of superphosphate, manufacturers print instructions for using a fertilizer made by a specific manufacturer, since the percentage of nutrients varies and different doses of the drug are required.
The main ways of feeding:
- the introduction of the drug in the autumn for digging;
- adding top dressing when planting seedlings and seedlings in spring in holes and pits;
- mixing with humus or compost;
- sprinkling soil next to plants;
- liquid plant nutrition during the growing season.
Monophosphate is introduced only a month after the addition of acid-neutralizing substances, so that the neutralization reaction has time to end. If the deadlines are not met, phosphorus compounds will react and form other substances that plants are not able to absorb.
Solution
If the first methods are quite simple and understandable, then with the latter, gardeners constantly have the question “how to dissolve superphosphate in water.” Microelement compounds are not visible to the eye, and a large amount of ballast gives the impression that monophosphate is not soluble in water. Although the instructions for superphosphate fertilizer indicate that it is highly soluble in water. Due to the fact that phosphorus deficiency is noticed when there are already obvious signs on plants, people have a desire to correct the situation as soon as possible. But there is no way to quickly dissolve superphosphate in water. Or the “speed of dissolution” depends on subjective sensations. It takes about a day to prepare the solution. Whether it’s fast or slow depends on personal perception.
The packaging says how to dilute superphosphate for top dressing, but it says simply: “dissolve and pour.” Such an indication brings gardeners almost to tears: “He does not dissolve.” In fact, gypsum does not dissolve. It shouldn’t dissolve.
But the process of extracting trace elements and necessary chemical compounds from porous gypsum granules is quite lengthy. Usually infusion for liquid top dressing is done within 2-3 days. A knowledge of physics will come to the rescue. The hotter the water, the faster the molecules move in it, the faster diffusion occurs and the faster the necessary substances are washed out of the granules.
One way to quickly dissolve superphosphate with boiling water:
- 2 kg of granules pour 4 liters of boiling water;
- stirring to cool and drain the resulting solution;
- pour the granules again with 4 liters of boiling water and leave to infuse overnight;
- in the morning, drain the water from the granules, mix with the first solution and bring the amount of water to 10 liters.
This amount is enough to process 2 acres of potatoes. Knowing how much dry fertilizer is needed for this area, you can calculate the proportions for other crops. In cold water, top dressing will need to be insisted longer.
Liquid top dressing can be prepared faster using the powdered form of monophosphate. But such a solution must be carefully filtered, since when spraying fertilizer, the spray nozzle may become clogged.
Dry fertilizer
When feeding plants with superphosphate in dry form, it is better to mix it with wet organic fertilizers and leave it to “rest” for 2 weeks. During this time, part of the nutrients of superphosphate will turn into compounds that are easily digestible by plants.
acidic soils
Since the characteristics of superphosphate depend on the additional substances contained in the product, the amount of ballast and the form of release, for the greatest efficiency, fertilizers must be selected under the soil of a particular area. So on acidic soils of the non-chernozem zone, it is better to use a sparingly soluble form in the form of granules. This land needs to be periodically deacidified. Semi-soluble is best used on alkaline and neutral soils.
Reduce the acidity of the soil with the help of alkaline substances: chalk, lime, ash.
In very acidic soil, a significant amount of alkaline reagents may be required. But usually it is enough to add half a liter of lime infusion or a glass of ash per square meter of soil.
Reviews
Conclusion
Superphosphate is one of the most popular, cheap and easy to use fertilizers. Its plus is that with the full provision of plants with phosphorus, the fertilizer does not contain a large amount of nitrogen, which causes the plants to rapidly grow green mass instead of flowering and fruit set. At the same time, garden crops do not remain completely without nitrogen either.