Phosphorus is one of the most important elements for the metabolism of plant organisms, in plants it presides over the flowering and fruiting phases, so it is easy to imagine how important it is for the vegetable garden.
This element is of organic origin, if it is not added through fertilization it tends to be scarce due to the consumption of the garden plants. A lack of phosphorus can be recognized by observing changes in the colors of the leaves, in reddish or tending to brown-purple tones.
Phosphorus is one of the most important nutrients among those that garden plants need, together with potassium and nitrogen they are considered the fundamental macroelements for the soil in agriculture.
The phosphorus in the soil
Phosphorus (P) is an element found naturally present in the soil, thanks to the numerous phosphatic minerals (mineral phosphorus) and the presence of organic matter (organic phosphorus). The pH of the soil plays an important role in allowing the root system to absorb phosphorus, because it conditions the activity of the microorganisms that transform the element and make it available for plants. This element is crucial for many vital operations of plants, the greatest demand for this substance occurs in the flowering phase and above all in fruiting.
Deficiencies and excesses of phosphorus
Shortage. This element is rarely lacking, it is present in practically all organic fertilizations and except in cases of heavily exploited land there are no phosphorus deficiencies in the garden. When phosphorus is lacking, the plant finds it difficult to grow and form roots, it stops blooming and does not form fruit. External symptoms that can make us understand the deficiency are abnormal coloration of the leaves (necrotic or red brown) and yellowing at the ribs. A ph value that is too high can inhibit the absorption of this element and be the cause of the deficiency.
Excess. The presence of a lot of phosphorus in the soil would not be a problem for the plant, were it not that this excess can make it difficult to assimilate other important elements (such as iron or nitrogen) and therefore indirectly be harmful.
Provide phosphorus with fertilizing
Phosphorus is present in all organic fertilizers used for the organic garden, by distributing compost or manure in the soil, phosphorus is also added. It is therefore not difficult to bring this element to the field to be cultivated. In agriculture, a specific phosphate fertilization can be useful during the summer to increase the flowering of fruit vegetables, but this is not an operation that I would recommend doing in the garden. Also because you should make sure you use fertilizers of natural origin, allowed in organic farming. If a good basic fertilization is implemented before sowing, the phosphorus provided is more than sufficient.