EcoFertil - Use of coffee by-products as an alternative for crop nutrition; Coope Tarrazú, Costa Rica

Written by Master Jimmy Porras Barrantes, Coope Tarrazú, Costa Rica

CoopeTarrazú is the largest coffee cooperative in Costa Rica, with about 5000 associated small coffee producers, which processes about 16% of all the coffee produced in Costa Rica.

In CoopeTarrazú, harvests equal to or greater than 275,000 bags of coffee have been maintained in recent years, from which up to 30,000 tons of coffee pulp has been removed annually. Since the 2013-2014 harvest, the cooperative has carried out Carbon Footprint measurements which determined that the management of this by-product generated about 80% of the total greenhouse gas (GHG) emissions of the cooperative.

Despite what this great challenge implies, for several years the cooperative has made technological advancements in pulp composting, generating a biofertilizer which then returns high quality material to the soils of the farms of the producers associated with the cooperative.

The primary purpose is to convert the pulp into a good quality organic fertilizer in the form of a soil amendment, which returns organic matter and nutrients to the soil to improve its physical and chemical characteristics. This has a positive impact, not only in terms of the increase in productivity, but also on the reduction of synthetic inputs and consequently on the conservation of the soils.

The organic fertilizer produced by CoopeTarrazú is made up as follows:

mg/kg
N: 1,89   
P: 0.18  
CA: 0,98  
MG: 0,33  
K: 3,16  
S: 0,19
FE: 40796  
CU: 64  
Zn: 67    
MN 796    
B: 28

Today the coffee producers of Costa Rica face the same challenges as agricultural producers all over the world, that being to maintain adequate production of their crops, and therefore they must change their approach in order to continue with their activity.

Currently, the prices of nitrogen fertilizers have tripled due to different factors such as COVID-19, the conflict between Russia and Ukraine, and to the high transport costs given the increase in the price of fuels.

These factors have an impact on the soil management of the farms of the cooperative members. It has been very well established by the technical team that in addition to having old soils with heavy textures and low fertility, one of the main problems presented by the soils in the region of Los Santos is the deficiency of organic matter. For this reason, the application of microorganisms and organic fertilizers is very relevant.

In light of this, new production processes have been developed, which allow the organic matter generated in the industrialized processing of the coffee fruit to be repurposed for the formulation of a new product, one which meets the needs of coffee producers and contributes an alternative to traditional chemical fertilizers, at a more affordable cost.

The new product developed by CoopeTarrazú starts from an organic matrix based on coffee pulp, which is then enriched to give other characteristics to the material, and generate a new product that is to be incorporated into the coffee plantations of CoopeTarrazú Associates. In the process of formulating the soil amendment, mineral sources must be incorporated into this organic matrix. However, each mineral source must be added at the right time, so that it affects the biochemical reactions in the pulp maturation process to the least possible degree.

For example, mineral enrichment can be carried out at the beginning or the end of the organic matter composting process, depending on the desired objective; in this case the addition of mineral sources to the organic matter was carried out with the objective of improving soil structure.

At this point, it must be understood that the combination of minerals added to the organic matrix is undertaken in order to reap the greatest benefits of both the organic and mineral components. Therefore, the organic matrix enriches the crop with large quantities of high quality organic matter, and the matrix's interactions with the minerals allow for their controlled release of the minerals in question. At the same time, the minerals support the presence of organic compounds.

The minerals that are used to enrich the organic matrix are sourced from raw materials that are already available on the market, these sources can be varied depending on the particular needs of each crop or the characteristics of the soil to be treated. 

For example, one particular product was formulated to supplement high amounts of organic matter with calcium and magnesium in particular, as a deficiency in these specific elements has been identified as a limiting factor to coffee production in the Los Santos region. 

The soils in the Los Santos Region are classified as Ultisols. Ultisols are characterized by low levels of organic matter, and lacking minerals like calcium, magnesium, zinc, and boron. Furthermore, the high slopes in which the coffee is cultivated are subject to erosion and leaching of nutrients, compounded by the exploitation of the soil over 50 or 100 years of continuous cultivation. In this case, the final composition of the EcoFertil product is as follows:

For CoopeTarrazú, being able to help the farmers associated with the cooperative is of vital importance, for this reason, the developed product is available for sale at a highly competitive price; each 40 kg bag of EcoFertil costs $7, which makes the product very accessible.

To purchase the product, the members of the cooperative, and producers in general, can access four different stores belonging to the cooperative in order to acquire the product. In addition, as part of this project, the cooperative has delivered more than 8,000 bags of product  directly to farmers so that they themselves can carry out tests on their coffee crops and verify the benefits that this product brings to their yields.

Currently, EcoFertil seeks to reduce the applications of industrial fertilizers and gradually reduce dependence on these products. By giving added value to coffee by-products, this project meets specific needs of farmers by addressing key strategic metrics for coffee production, encompassing environmental, economic, commercial, and social concerns. Additionally, the project supports public policy that Costa Rica has promoted with the aim of decarbonization of the economy, the use of biomass available in the agricultural sector, supporting the national Bioeconomic strategy and the Sustainable Development Goals promoted by the UN.

The cooperative hopes to be able to process and formulate the EcoFertil product with at least 40% of the coffee pulp in the next four years.

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For additional information see "Ecofertil: improved amendments for coffee cultivation".