Phosphate rock as a fertilizer: composition, properties, application technology

Fertilizers and preparations

Phosphate rock production uses natural substances containing the primary chemical element. These components are first enriched, then ground into a powder and packaged.
In agriculture, phosphate rock is used as a primary fertilizer on chernozem and red soils, which helps plants better absorb chemical elements beneficial for growth and root system development.

Phosphate rock: composition, formula, properties, application

The substance is a finely ground grayish or gray-brown powder—the sieve residue is no more than 10%, consisting of grains approximately 0.18 mm in size. Phosphate rock flour does not cake, is not dispersed by wind, and has an intrinsic moisture content of no more than 1.5%. It does not absorb water from the environment.

This powder contains at least 17% phosphorus oxide itself, the remaining mass is made up of elements necessary for plant growth and increased yield, as follows:

33% calcium;
0.6% magnesium;
2.3% iron;
1.6% mixture of potassium and sodium;
35% silicon dioxide and other elements.

The ratio of all nutrients in rock phosphate is close to that found in fertile soil, allowing this fertilizer to be applied every few years. Furthermore, the phosphate component of the supplement is of the citric form, making it ideal for acidic soils.

It is applied as deeply as possible during spring or autumn pre-sowing tillage. Phosphate flour is not washed away by water and does not spread well in the soil, so its location in the soil should be as close as possible to the future roots of plants.

Signs of phosphorus deficiency

A deficiency of this micronutrient manifests itself as darkening of plant leaves, with bronze and purple hues at the bases and petioles. Growth and ripening are slowed, and the number of ovaries on bushes and branches decreases. Plants in acidic soils with low organic matter most often suffer from this type of phosphorus deficiency.

In older perennials, this type of phosphorus deficiency can manifest itself after several years—old branches give up all their vitality to the young, making it difficult to save such a plant. At the first sign of phosphorus deficiency, a quick fix can be achieved by dissolving 20 g of potassium monophosphate in 10 liters of warm water and watering the area around the trunk.

If the soil around a tree or bush is acidic, phosphate should be added. If the soil is depleted, superphosphate should be applied at a rate of 50 g per bucket of water. The crowns of trees and shrubs should also be sprayed with this solution. After two weeks, liquid organic fertilizers, such as manure or compost solutions, should be added as a nitrogen supplement. The amount of organic matter required depends directly on the properties of the plants being cultivated and the quality of the soil.

Fact! You cannot add phosphate flour together with lime or dolomite flour - this will negate all the work to enrich the soil with the necessary element.

Positive features

Experts say composting manure is the ideal application. This increases the phosphorus content of this organic fertilizer and reduces nitrogen loss during the decomposition of materials of varying densities. 30 kg of powder is required per ton of organic matter.

Attention! Using phosphate rock on neutral and alkaline soils will not produce results, but when applied to highly acidic soils, it guarantees increased nutrient content in the fruit and significant resistance to disease, climate change, and rot.

This fertilizer does not harm plants or the environment even at high concentrations, so it is enough to use it once every 4-5 years during autumn digging or spring cultivation.

Fertilizing with grass

Proponents of organic vegetable growing recommend preparing a fermented herbal infusion from weeds. To do this, coarsely chop the collected plants, fill a barrel 2/3 full with them, and add water. After the mixture has fermented, dilute a small amount of rock phosphate with warm water until it forms a suspension and add it to the solution. For root feeding, use 1 part of the solution per 10 liters of water, and for spraying on the seedlings, use 1 part per 20 liters of water. Complex mixtures containing other essential micronutrients can also be added.

Security measures

Phosphate rock is a mildly toxic fertilizer, so when handling it, wear personal protective equipment (PPE)—gloves, respirators, protective suits made of thick fabric, and safety glasses. After handling, maintain personal hygiene—shower, wash your face and hands with soap.

If the powder comes into contact with exposed skin, wash it with warm water and soap. If you accidentally inhale the flour, rinse the mucous membranes with plenty of water and seek medical attention. The same should be done if the flour gets into your eyes.

The substance should be stored away from animals, food products and feed, and in places inaccessible to children.

Reviews

Nikolay, Smolensk region:

"Back in the 19th century, progressive landowners began using rock phosphate to enrich depleted soil. I applied the prescribed amount of fertilizer to the site of an old garden, uprooted as unnecessary. The soil was so poor that even weeds barely grew. The result exceeded all my expectations – I harvested 10 times more potatoes than I planted – from one bucket of planting material, I got 12 buckets of choice tubers."

Viktor Sergeevich:

"I've been adding rock phosphate to my compost mix since Soviet times. The fertilizer is top-notch—I even went to the local lab to check it."

Marya Ivanovna:

"A neighbor recommended fertilizing the old apple tree in the fall after pruning it for rejuvenation—it was a very good variety, but the tree had practically degenerated. After the work, the tree surprisingly blossomed and produced a bountiful harvest. I credit this fertilizer with the revival of my beloved apple tree!"