Emission-reducing coffee farming: [1] Dual benefits of going organic

Editor's note: Emission-reducing coffee farming isn't just a story about the environment. It's also a solution for cutting costs, protecting resources, adapting to climate change, and meeting import market requirements. As science proves itself in the field and gains acceptance from businesses and farmers alike, Central Highlands coffee gains a stronger foundation to raise its value and grow sustainably.

Organic farming cuts chemical fertilizer use by more than 70 percent

With more than 20 years in the trade, Phan Huu Duong of Ia Ping hamlet (Ia Ly commune, Gia Lai) has ample experience getting the most out of his family's five hectares of coffee. In his early years farming, believing his coffee garden had to hit the highest possible yield, Duong spared no expense buying chemical fertilizer to feed his trees.

He didn't realize at the time that this approach was raising his costs, hardening his soil, wearing out his trees faster, and, notably, releasing large amounts of carbon into the environment.

His approach began to change after he took part in training on the 4C sustainable coffee farming program in 2008. From there, Duong gradually shifted toward organic methods, building his approach around improving the soil and establishing an ecosystem within the garden: planting shade trees, maintaining ground cover to retain moisture and prevent erosion, and making his own organic compost to feed back into the garden.

"I use coffee husks, leaves, grass, and other agricultural byproducts to make compost, adding nutrients and improving the soil. Grass in the garden is kept under controlled growth to limit erosion during the rainy season, retain moisture in the dry season, and add organic matter that creates a favorable environment for beneficial microorganisms," Duong said. He noted that his family now uses less than 30 percent of the chemical fertilizer it once did, applying it mainly at times when the coffee trees need extra nutrients for growth, fruiting, and maintaining yield.

Organic coffee cuts on-farm emissions by 60 to 70 percent

According to research from the Western Highlands Agriculture and Forestry Science Institute, chemical fertilizer currently accounts for 70 to 75 percent of coffee's emissions. Do Van Chung, Deputy Head of the Institute's Agricultural Systems Department, said that in conventional coffee farming, nitrogen-based fertilizer is typically the largest source of greenhouse gas emissions. Emissions also arise during fertilizer production and transport, and nitrogen, the main component of nitrogen fertilizer, can transform in the soil after application into N2O, a greenhouse gas with a very high global warming potential.

Coffee farming also generates emissions from other sources, including electricity or fuel used for irrigation pumps, machinery operation, pesticides, burning of branches, leaves, and other residue, wastewater from wet processing, and transport of materials and products. "Our research on coffee gardens shows that organic and inorganic nitrogen are the main contributors to the carbon footprint, so managing and reducing chemical fertilizer use is the most important measure for cutting emissions in a coffee garden," Chung said.

Producing organic coffee requires strict adherence to procedure. It starts with surveying the garden, analyzing soil and water sources, and mapping the production area. The garden must have a buffer zone to limit the risk of chemical cross-contamination from outside, a shade-tree system at an appropriate density, and maintained ground cover to prevent erosion. Weeds are managed through mowing and mechanical weeding, without herbicides, and no pesticides are permitted.

"Pests and disease are managed through integrated methods, including field sanitation, pruning for better airflow, conserving natural predators, and using approved biological products. Fruit is picked only when ripe and kept separate from conventional coffee. Preliminary processing must conserve water, treat wastewater, and make use of fruit husks for compost production. All inputs, fertilizer applications, care activities, harvesting, and output must be recorded for traceability," Chung said.

For organic coffee nutrition, growers use well-composted manure, microbial organic fertilizer, and compost made from coffee husks and plant residue. Organic fertilizer must be properly composted, with controls for pathogens, weed seeds, and contamination risk; growers targeting exports to Japan, the United States, and the EU need fertilizer products certified to European and U.S. standards (USDA-NOP). For gardens transitioning toward organic, emission-reducing methods, reusing coffee husks, manure, and other residue can replace roughly 30 to 50 percent of mineral nitrogen in the early stage, moving to 100 percent certified organic and microbial organic fertilizer by the third year.

Chung said organic farming cuts on-farm emissions by about 60 to 70 percent compared to intensive farming that relies heavily on chemical fertilizer. The actual reduction depends on how much nitrogen is replaced, yield, composting methods, irrigation, and the soil's carbon-storage capacity. Studies have recorded a carbon footprint of about 0.12 to 0.52 kg CO2e per kilogram of fresh fruit for organic coffee, compared to about 0.26 to 0.67 kg CO2e per kilogram for conventional coffee.

Economically, spending on chemical fertilizer, herbicides, and pesticides can fall, but labor costs and expenses for compost production, record-keeping, inspection, and certification typically rise. During the transition period, yields may dip if organic nutrient sources don't yet meet the trees' needs. But once the soil improves and the market stabilizes, growers can benefit from higher sale prices, reduced dependence on purchased inputs, and less exposure to fertilizer price swings.