Learn about these 4 types of organic fertilizer and how to use them!
Very well regarded in agriculture, organic fertilizer can be of animal origins, such as cattle, chicken and swine, or plant origin, from plants and cultural remains. As Daniel Petreli, an Application Technologies Specialist at Jacto, explains, “when we talk about organic fertilizer, it is always something that comes from the decomposition of some material”.
There are different types of fertilizer, with distinct applications depending on the material used for production. In this article, you will better understand the main types of organic fertilizer and how to handle each of these products. Keep on reading and to find out more!
What types of organic fertilizers are available?
There are several ways to obtain organic fertilizer. Below, we’ll consider some of the more common types.
1. Compost and earthworm humus
Composting is a method that uses the decomposition of organic waste, such as dry leaves and food, to create a natural fertilizer. It is a great way to recycle waste that would otherwise be discarded, taking advantage of its nutrients to assist in the proper development of plants.
The compound used may be of plant or animal origin. However, before being used in fertilization, it needs to go through the decomposition process. This is necessary so that the nutrients in the materials become available for absorption without interfering with the soil microbiota.
For the process, overlapping compost bins, or composters, are used, as follows:
- the bottom of the first box is lined with leaves, and organic material is deposited above the leaves;
- in a second box, below, humus and earthworms are deposited. They help with decomposition;
- in the third and last box of the pile, the liquid fertilizer produced by the process (leachate) is stored.
Compost is an excellent fertilizer for plants. In general, it is used in gardens. Farmers prefer to put the compost on the ground and then plant the seedlings. Others put it on the soil. Both methods give good results.
This process takes two to three months. Therefore, it is essential to ensure correct maintenance of the composter during this time to guarantee the health of the earthworms and the proper functioning of the digestive boxes. One of these important actions is aeration.
Adequate aeration ensures the presence of oxygen in the compost, facilitating the decomposition of materials and preventing the production of odors that could attract flies and other insects.
The first aeration takes place about 15 days after composting starts, when the material is hot. For this, it is necessary to turn over the organic material. After that, this procedure needs to be repeated weekly.
2. Manure from herbivorous animals
Manure comes from various animals, such as poultry, cattle and swine, and is the most traditional organic fertilizer. It is widely used in vegetable gardens and plantations in general, as it has a high potential as a fertilizer, especially when mixed with other types of organic fertilizers.
Before being used, this type of fertilizer needs to undergo a previous composting process since there is a risk of contamination by harmful microorganisms present in the feces. These wastes are added to materials on the ground and then turned over every three days, preventing them from getting too wet. It takes about a month for the fertilizer to be ready for application.
3. Grass
Cut grass is a great material for mulch in a vegetable garden. It can provide essential nutrients to plants, such as nitrogen, and form protection to preserve soil moisture and reduce fungi action, weed growth and insect proliferation.
Its application is very simple: just take the freshly cut grass and spread it across the plantation. Another advantage is the low cost, especially in the short term. Because it is light, it is suitable for practically all types of plants. However, use it only when very dry, as its underside can mold and contaminate the soil.
4. Sewage sludge
Petreli highlights that “sewage sludge is being studied as organic fertilizer”. Although the sewage itself does not benefit plants, the sludge resulting from the treatment process does. Here we have an organic and low-cost material rich in carbon and nitrogen, which are highly beneficial for the soil.
Therefore, the use of sewage sludge in agriculture guarantees good results both in terms of sustainability and plant nutrition. On the other hand, pay attention to the risks of contamination by nitrate, toxic organic products and heavy metals.
The Ministry of the Environment of Brazil created rules through Resolution 375 so that the practice could be standardized, ensuring safety throughout the process. Thus, when the residue is treated and biologically inactivated, it can be used in the soil.
How do I know which is the best organic fertilizer for my crops?
The expert explains that “normally, registered organic fertilizers come with a report of the minimum nutrient conditions they have. Then we use the dosage that is appropriate to the needs of each culture”. Therefore, it is necessary to analyze the guarantee offered by companies on the reported nutritional conditions.
Petreli emphasizes that “companies must be reputable, provide a good analysis, conditions and traceability of the materials. They must provide a list of the minimum nutrient conditions offered by the materials”.
Another point highlighted by the expert is that if the production of organic fertilizer is homemade, “it is important to be mindful because the materials undergo processes of fermentation, decomposition and, later, mineralization. The right procedures must be respected to avoid contamination or toxic effects. It must go through the process of decomposition and mineralization to be of good quality.”
Petreli adds that sometimes it takes many months for the material to ferment. The temperature will change, so you must ensure that the environment is ideal for decomposition. It may be necessary to moisten the material, separate the decomposed part with another and mix various materials to form the compost that will be used later.
Although it is possible to produce organic fertilizer on a rural property, it is important to seek alternative fertilizers on the market to ensure higher quality.
Organic fertilizers are great alternatives to meet the nutritional needs of plants. When associated with other fertilizers and application technologies, these products can significantly increase the property’s productivity.
Do you know other types of organic fertilizers that are beneficial to rural producers? Let us know in the comments!
Interviewed: Daniel Petreli, Application Technology Specialist at Jacto.