By the method of production, all modern complex fertilizers are divided into mixed, complex and difficult-mixed. The second is usually attributed to such as ammophos, potassium nitrate, diammophos. These drugs are obtained as a result of the chemical interaction of the components. Microelements, herbicides and some pesticides are introduced into the composition of liquid and solid complex fertilizers.
Combined (complex-mixed) include complex fertilizers, which are obtained as a result of a single technological process. Such chemicals in one granule contain two or three basic nutrients important for plant development in the form of compounds. Combined include: nitrophoska and nitrophos, nitroammophoska and nitroammophos, potassium and ammonium polyphosphates, carboammophos, liquid complex mixtures.
Mixed are called formulations of simple fertilizers, which are obtained in the process of dry mixing.
Complex-mixed and complex mixtures are characterized by a high content of nutrients, while they are very economical to use.
Despite all its advantages, complex fertilizers have one significant drawback - the proportions in the NPK content in them vary within fairly narrow limits.
In complex preparations, the percentage composition of the constituent elements is usually strictly observed, however, if some changes are required, then, after making simple calculations, these changes can be made independently. For example, if complex fertilizers for vegetables do not contain enough nitrogen, then you can add a simple chemical with a high nitrogen content to them, but only professional agricultural technicians can reduce the content of this or that component.
At the time of digging the earth in the spring or autumn, for the effective enrichment of the soil with minerals, you can use preparations with a high content of such a substance as calcium carbonate, which perfectly dampens acidity. This is especially important for those areas where tomatoes are located.
Complex fertilizer for tomatoes with seedling method of cultivation is applied when planting seedlings in the ground. 500 grams of humus mixed with one tablespoon of ash and one teaspoon of superphosphate are added to the plant well. Fertilizing tomato seedlings can be carried out already ten days after its planting and rooting.
The first time tomatoes are fed with mullein, and complex fertilizers can be applied already during the second such procedure.
Double and regular superphosphate are the most popular and common drugs used in planting tomatoes. The composition of these chemicals includes: phosphorus, calcium, sulfur, magnesium and nitrogen. Each of these elements has its own beneficial effect. So, calcium effectively reduces the acidity of the soil, and magnesium is simply necessary for nightshade plants for normal and active development. Complex fertilizers are usually available in the form of powder or granules.