Origin of the humus theory explains how complete fertilizer works
In the 19th century, people noticed that after a few years of cultivation, fields did not produce as much crops as they did at first. However, they still had no knowledge of nutrients, which is why they could not explain this. If the fields were not cultivated for a few years, the yields increased again. This ensured that scientists such as Albrecht Thaer put forward theses as to why this was so. A humus theory emerged, which held that plants fed on decaying animals and plants. Since something was taken from the field during the harvest, there was an imbalance in the cycle. According to the theory, something "dead", i.e. rotting plant parts or animal parts in the form of humus, has to be added to the soil so that new "life" can grow again. Humus is dead organic matter in and on the soil. With the humus theory, soil fertility was equated with the humus content of the soil.
Theory of mineral nutrition - this is how organic and mineral arose NPK -Fertilizer
In 1850 the humus theory was replaced by the theory of mineral nutrition. The German chemist Justus von Liebig realized that plants do not feed on humus itself, but on the minerals it contains. So if a field produced no or less yields, then it was because chemical elements were missing in the soil. In the course of this, Liebig also recognized that chemical analyzes could be used to determine which minerals were missing in the soil and then to introduce them into the soil in a targeted manner. This was the origin of the fertilizer and the relevance of the nutrients nitrogen, phosphorus and potassium (NPK) was also recognized in this context.
Fertilize the minimum law according to Liebig about plants
The same scientist also popularized the minimum law, also called Liebig's minimum law or minimum factor. However, it was published as early as 1829 by another scientist named Carl Sprengel. Carl Sprengel recognized that plants need 12 minerals for their growth and cannot grow if one of these substances is completely missing. If a substance is only present in small amounts, the plant will also grow poorly. Finally, Justus von Liebig's law of the minimum shows the connection between plant growth and the factors that influence it. The growth of plants is determined by the scarcest available resource. This resource is also known as the minimum factor. It can be nutrients, but also water and light. The minimum factor is therefore the limiting element that affects the overall growth of the plant, regardless of whether all other required resources are available.
The law of the minimum: Example with NPK -Fertilizer
A plant is in a place where there is not enough light and has met 70% of its nutrient requirements. Now fertilizer is added and the plant reaches 100% of its nutrient requirements. However, the growth of the plant does not improve because the minimum factor is the light. A plant therefore only develops as far as the scarcest resource allows.
What does the optimum law say?
In 1895 the minimum law was extended by the optimum law by Georg Liebscher. It states that there is an optimum of growth factors at which the plants grow fastest. A minimum factor therefore has a more negative effect on the growth of a plant the closer all other factors are to the optimum.
What do the laws mean for our plant care? - Tips for using NPK fertilizer
The law of the minimum forms an important basis for the use of fertilizers. It shows that regular fertilization is essential for continuous plant growth. Since it is particularly important to provide plants with all the necessary nutrients in a form that is available to plants, care must also be taken to ensure that there is an adequate supply of micronutrients. It should also be noted that regular fertilization can only help plants grow if the plant is given a location tailored to its needs. Depending on the type of plant, sufficient light, water or dryness must be provided for the fertilization to have an effect.
Pros and cons of NPK -fertilizers
NPK fertilizers are organic or mineral fertilizers that contain the most important nutrients called nitrogen, phosphorus and potassium. A big advantage of these fertilizers is that they enable plants to be supplied with basic nutrients that meet their needs. In addition, the appropriate composition promotes fruiting and growth of indoor plants, vegetable crops, lawns and flowering plants. Fertilizers with a long-term effect offer a permanent supply to the plants. A disadvantage of applying fertilizers can be the leaching. Organic-mineral fertilizers contain artificial and natural components - they are more expensive compared to pure organic fertilizer. Overall, the choice of fertilizer depends on many factors, such as the soil type and the needs of the respective plants.
Composition and application of NPK -fertilizers
The three main nutrients nitrogen (N), phosphorus (P) and potassium (K) are essential for the growth and development of indoor plants and promote the formation of leaves, roots and flowers. Natural fertilizers can be of animal or vegetable origin. They also contain other important nutrients and micronutrients required for healthy plant growth. They offer a sustainable option for fertilizing houseplants as they gradually release nutrients and contribute to soil fertility. The application of NPK organic fertilizers for houseplants should be done according to the directions on the packaging or according to the needs of the specific plant species to avoid over-application. The application of liquid fertilizer is recommended, because this can be easily dosed and strengthens the plants very quickly.
You can find a suitable fertilizer for your plants among the FARBIO® organic liquid fertilizers .
