How climate change is redefining the coffee story

Climate change impact 
A study of the global impact of climate change predicts that climate pressure could reduce the area suitable for coffee production, especially, Arabica, globally by 50 percent by 2050. 

Arabica coffee is grown in high altitude areas (above 1400m), but this altitude threshold is likely to move up, if temperatures rise. The coffee farmers, who toil every day to give us a good cup of coffee, are already feeling this brunt.

Ms Janet Nabutuwa, a coffee farmer and member of the Namayonyi Shalom Coffee Farmers Group, narrates her frustration growing coffee amid changing weather patterns. 

“I grew up seeing my parents grow coffee, and when I got married, I chose to emulate them by growing more coffee. But I had never experienced such challenges of extreme weather conditions,” she notes.

“Sometimes, we experience prolonged dry seasons, while the rain season is shorter. This seriously affects the coffee. I cannot recall how many times, I have replaced seedlings as a result of prolonged drought,” says Nabutuwa.’

Nabutuwa’s experience is not very unique from other farmers in her region and beyond, whose farm size is less than two hectares.

Rainy seasons 
Augustine Wodeya, a coffee farmer in Busulani, Sironko District, says the changing rainfall patterns cause uncertainty on seasons. “It is increasing becoming difficult to know when to plant coffee. We have to keep buying seedlings to replant since some of them dry up after planting,” he notes.

Wodeya also observes that the droughts have become longer, yet the rains were shorter, and rainfall during the rainy season was becoming more erratic.

Historically, the rainy season in Uganda is between March till May and October till November. Light rain season falls in November and December.

Dry seasons are from December to February and June to August.

Effects 
Uganda is facing significant effects of a changing climate; increased frequency of extreme weather events such as floods, drop in water levels, changing weather patterns, as well as drought, whose social economic influences make farming communities very vulnerable.

The country is ranked as the 15th most-vulnerable country to climate change globally, and the 49th least prepared country to combat the effects, according to the Notre Dame Global Adaptation Initiative Index (2019) ranks Uganda. 

Indubitably, the frequency and severity of extreme weather events, have a significant impact on agriculture with long-term implications of poverty and increased food insecurity.

Dependency on rain 
The majority of smallholder farmers in Uganda, such as Wodeya, rely on the seasonal rains to ripen the coffee beans.

The price they get for their coffee is strongly influenced by bean characteristics such as size and minimal defects, which are largely influenced by the amount and timing of rainfall.

Ms Lorna Kwaka, an agronomist at the National Coffee Research Institute (NaCORI), says too little rainfall during the growing season stresses plants, which may cause branch death, defoliation or reduce resources for fruiting.

This, she adds, may lead to small and damaged coffee beans.

On the contrary, Kwaka, notes that high temperatures can accelerate berry development and ripening, reducing bean filling and in turn causing smaller bean sizes.

“Unfavourable rainfall and temperature can also promote the conditions that damage and discolour coffee beans. Too much rainfall can dislodge flowers and fruits, or if heavy rain occurs during harvest, increased moisture favours conditions for mold growth, disease and excessive fermentation, all of which may increase coffee bean defects,” says Kwaka.

Experts warn of severe weather 
Experts have warned of longer and more extreme periods of drought and rain, making farming even harder. This is likely to distress the volumes of coffee produced. 

According to Uganda Coffee Development Authority, Uganda’s coffee volumes have steadily increased from about 3.5 million 60kg bags in FY 2014/15 to 6.14 million 60 kg bags in FY 2021/22.

Dr Godfrey Sseremba, an agronomist and senior research officer at NaCORI, says; “We can no longer just rely on ‘our fertile land and favourable climate’ to grow coffee. We need to adapt to a changing climate by embracing use of quality planting materials, water conservation and shade technologies.”

Advice 
In the face of a changing climate, smallholder farmers such as Mutuwa and Wamai, whose return on investment in coffee is steadily declining, prompting them to abandon coffee for other crops, need locally available and sustainable adaptation strategies.

One such strategy is planting shade trees in their coffee gardens. According to Dr Sseremba, shade can reduce temperatures in the coffee canopy by up to 2°C. Shade trees and crops such as bananas help to adapt the coffee systems to increasing temperatures, but also provide additional food and income.

Recommendations 
The National Coffee Research Institute has recommended shade trees species for each of the six coffee-growing sub-regions in Uganda.

The most common tree species that farmers are familiar with are mugavu (Albizia coriaria) and mutuba (Ficus natalensis).

Some farmers, especially in coffee-growing areas in Central Uganda, best describe the former as Omugavu Omuganda. Farmers need to appreciate the pluses and minuses of intercropping such trees and other crops in their gardens, especially as production areas become drier and hotter.

The decision about which shade tree to intercrop with coffee should be informed by facts. According to studies by NaCORI, Some tree species have been found to be alternative hosts to pests that adversely affect plant yields.

The damage caused by pests such as the Black Coffee Twig Borer to Robusta coffee production, for instance, is likely to increase as the climate warms because these suck sap from the plant and reproduce rapidly during such seasons.

Agronomy 
Dr Sseremba also notes that adding shade or shade crops to a coffee system increases competition among the different plants for water, nutrients and light. 

But he advises that this should be managed by using good agronomic practices such as soil and water conservation practices, integration of fertilisers and organic nutrient inputs.

Farmers also need pest management tactics that accentuate use of locally-available materials.

Such often turn out to be affordable, sustainable and environmentally-friendly. They do not encourage use or spraying of man-made chemicals, which is desirable in organic coffee farming.

Methods such as trapping the insect pests; using natural pesticides extracted from plant or animal origins; planting other plant species on-farm to repel off the dangerous pests are some of the farmer-friendly means that can be explored.

As Ugandan researchers work toward developing varieties that are drought-tolerant, farmers could undertake sustainable, affordable and environmentally-friendly means to cushion their plants against extreme weather changes.

This could enhance their crop yields and hence improve their livelihoods.

Breeding drought resistant coffee
Researchers at NaCORI have started gathering and storing coffee germplasm from natural forests in Uganda.

Work on setting up field gene banks for germplasm conservation both at Kituza (Robusta) and Bugusege (Arabica).

More than 20,000 stem cutting of about 120 Arabica coffee genotypes have been initiated for rooting. A total of 60 accessions of Arabica coffee have been secured in field gene bank at Bugusege. 

These efforts, according to the Director for Research, Dr Geoffrey Arinaitwe, are likely to unveil a range of previously unknown drought-resistant genetic profiles, which could save the livelihoods of thousands of coffee producers.

Some of this wild coffee germplasm is potentially resistant to climate change.

“We have identified materials from wild coffee varieties that are drought-tolerant and have studied them to understand their composition,” he explains. 

“The materials naturally grow in Ugandan forests and within their germplasm there is diversity which is drought-tolerant,” he adds.

Research work is ongoing to cross the wild varieties with the improved coffee wilt disease-resistant Robusta varieties.

The hybrids are then grown in greenhouses and in other water-stressed areas to observe their performance.

These unique genetic coffee materials from wild forests may help in the reproduction and development of drought-resistant coffee varieties.

Other areas of interest to the researchers are to establish other significant characteristics for the coffee sector such as the quality of the cup (taste), resistance to pests and diseases.

The results are expected in the near future.