Climate change threatens coffee production

A farmer looks at a coffee plant that has been attacked by the coffee wilt disease. File Photo.

What you need to know:

Uganda has the potential to produce much more coffee but a number of factors hinder the prospects, of which climate change plays a major role.

Current changes in climatic conditions are an increasing threat to coffee growing in the country. This would lead to a significant loss in incomes, given the fact that the crop is a primary export and thus, a principal foreign exchange earner.

Uganda, which grows Arabica and Robusta coffee, is among Africa’s top coffee producing and exporting countries.

Negative effects
Climate change has manifested itself in erratic rains, increasing global temperatures, pests and diseases, rampant landslides and long dry spells which all, according to agricultural experts, spell doom for Uganda’s future coffee growing.

Stakeholders, who include farmers, traders, experts, processors and exporters, acknoledge it has had a negative effect on production, that is, declining yields and an increase in low quality grades.

Mr James Ponde, a plant pathologist at Buginyanya Zonal Agricultural Research and Development Institute, which is located in Bulambuli District, says this has resulted into emergence of pests like the stem borer and diseases like leaf rust and wilt.

The coffee berry diseases affect 75 per cent of the plants in Bulambuli, Kapchorwa, Bukwo, Kween and Bududa districts.

Decline in yields
According to Uganda Coffee Development Authority, coffee wilt, which mainly affects the lowland robusta variety, has destroyed over 12 million plants since 1993.

Even though Arabica coffee, which is grown in the highlands, has not been greatly affected, its production accounts for 10 per cent. “Initially, coffee leaf rust disease was known to be found below 1,500 metres above sea level but is now attacking coffee grown at 1,800 metres and we attribute this to climate change,” Mr Ponde notes.

Since it attacks the beans, loss in yields can be as high as 100 per cent. However, diseases like leaf rust could also be caused by poor agricultural practices like failing to mulch the plantations and loss of spraying regimes. In the 2009/2010 season, 200,000 metric tonnes of patchment coffee was expected from Bugisu region but only 40,000 tonnes were realised, representing a shortfall of 160,000 tonnes.

Dr Africano Kangire, head of the Coffee Research Centre Kituza, says a slight increase of two degrees Celsius in global temperature will push the crop past its margins; only a few highland areas in Uganda could continue to grow coffee. “It is predicted that a two degree rise will reduce Uganda’s coffee production by 80 per cent,” he says.

Rise in temperature
Coffee will be restricted to only high elevation areas as the crop’s suitable climate migrates into the foothills of Rwenzori and Elgon. This means temperatures in the central region will be higher for the crop causing its exit since coffee is sensitive to water stress.

Hotter temperatures would also expose the crop to more pests and diseases. According to a 2007 meteorological report, the average temperature in the coffee-growing areas was at about 25 degrees Celsius.

But Mr Paul Isabirye, Assistant Commissioner, Department of Meteorology, says due to global warming, temperatures could have risen since the report was issued.

He points out that rain is now falling at the wrong times, and the coffee beans have less time to mature. “If the coffee beans face a lot of sunshine and less rain, the beans will be smaller and in lower yields,” he says.

Mr Cosmas Kanyike, procurement and logistics manager, Ibero (U) Ltd, says the company had targeted to buy 60,000 bags of coffee last year but only ended up realising 40,000 bags while Mr Iyer Suresh, exports manager at Olam (U) Ltd, says they projected to buy 20,000 tonnes of Robusta coffee in the same year but only managed to get 9,000 tonnes.

Others like Mr David Barry, acknowledge that the amount of low quality coffee has also been on the increase. “The long droughts that come when the cherries are not yet mature have greatly reduced coffee production,” he says.

Ms Mariam Nanangwe, a resident of Bugabwe village in Kaliro Town Council, who owns six acres of coffee and has been growing it for 20 years, says she has already begun feeling the effects of climate change.

In the past 10 years, her yields have dwindled from 70 bags she used to harvest each season to a mere 10 bags or even less a season.

Mitigation measures
“Diseases like leaf rust and wilt and pests like the stem borer and leaf bug have become rampant. Thirty years ago, the weather was cool and we used to get a lot of rainfall but there are long droughts which come sometimes during flowering,” she says.

“Coffee is my main cash crop and because I now earn little from it, I am finding it hard to sustain my family of six people.” Because she now earns little, she cannot afford to buy pesticides to spray her coffee.

Dr Kangire says, as a mitigation measure, new clonal varieties have been developed. Investigations on crop management practices including intercropping coffee with annual crops and coffee-banana inter-cropping systems, integrated weed management and use of organic fertilisers have been conducted.

“Alternative insect pests control measures, which reduce dependence on expensive chemical pesticides and are environmentally safe, for instance, biological control, are being studied,” he says.