For plant nutrition and soil improvement in organic production, organic, mineral, and microbiological fertilizers are used. Fertilization in organic agriculture is defined as the targeted supply of soil and the timely provision of plants with nutrients, taking into account their losses. In this way, priority is given to fertilizing the soil rather than fertilizing the cultivated crop. By using nutrients correctly, soil fertility is established at an agronomically and economically acceptable level, which is a prerequisite for successful organic production.
In organic plant production, the use of the following fertilizers of organic origin is permitted:
manure,
dried manure and dehydrated animal manure,
composted animal excrement, including animal manure and composted manure,
liquid animal excrement,
composted or fermented farm waste,
peat,
residues after mushroom production,
remains of dead worms and insects,
guano,
composted or fermented mixtures of plant matter,
products or by-products of animal origin,
products and by-products of plant origin for fertilization,
seaweed and seaweed products,
wood shavings or wood residues,
composted tree bark, wood ash.
If the farm does not have livestock, it is allowed to purchase organic fertilizers from other farms (traditional and organic) under control, where, among other things, proof is required that genetically modified organisms are not present in the fertilizer. Fertilizers originating from intensive systems are prohibited.
The use of organic fertilizers such as manure, compost, green manure, and vermicompost forms the foundation of the production of safe and healthy food, due to the potential negative effects that uncontrolled application of mineral fertilizers can cause. The prerequisite for successful production is combined crop-livestock farming, as only this can ensure nutrient cycling within the farm without large external inputs.
In organic production, the use of certain mineral fertilizers is also permitted: ground phosphate rock, aluminum-calcium phosphate, slag, crude potassium salts or kainite, potassium sulfate, with possible magnesium salt content, vinasse or extracts from vinasse, calcium carbonate, magnesium and calcium carbonate, magnesium sulfate, calcium chloride solution, calcium sulfate, industrial lime from the sugar industry, industrial lime from vacuum salt production, elemental sulfur, sodium chloride, rock dust, and clay.
Quality microbiological fertilizer should contain effective species and strains of microorganisms that will activate a specific microbiological process and provide the plant with nutrients. These microorganisms should have good survival and adaptation abilities to the new environment and specific soil conditions and have a high ability to compete with indigenous populations of microorganisms.
