Coffee Leaf Rust

Coffee Leaf Rust

Coffee leaf rust (CLR) is caused by a fungus Hemileia vastatrix and is the most important disease of Arabica coffee [2005, Illy, A. et. al.]. There is presently a significant outbreak in Central and South America where a great many of the world's finest coffees are grown.



One of the coffee merchants we work with is Melbourne Coffee Merchants and they recently provided this helpful update (below) based on their travels to the Pacas family farm in El Salvador.

Unfortunately, leaf rust is impacting all producers in Central America. We were there in March 2013 and saw the impact first hand. Some producers are managing it better than others (and luckily all of the producers we work with had a good handle on it) and the better run farms are currently investing a lot of hard work and money into mitigating the impact next year and the years that follow.

Attached are some pictures - one is of a leaf that has been affected by rust, the other is of a 'naked' coffee farm that has lost all of its leaves due to the rust. There were many farms like this in El Salvador and Guatemala and many had been abandoned. It was really upsetting to see.

There is also a photo that shows cherries collected from a farm that was severely affected by rust - this is their last pass of the season and you can see there is a lot of unripes as well as cherries that look like they are ripe but in fact are not ripe at all (even though the outside colour may be darker) - which obviously severely impacts the cup.

All of the farms that we work with were actively putting in place strategies to combat the rust. Some measures were to curb the immediate impact and other measures were to reduce the long term impact. There is a photo from the Pacas family attached which shows their approach which involves:

  1. Natural barriers (other trees etc. to improve the microclimate and diversity)
  2. Chemical control / fungicides (immediate measure)
  3. Pruning (immediate measure - which will impact yield but essential to allow trees to recover)
  4. Soil conservation
  5. Plantation of other varieties - in the case of the Pacas' farm, delicious ones like SL28 and Geisha not other rust resistant ones which are not so tasty such as Castillo

The general implication of all of this is that whilst the general commodity price for coffee is at an all time low, the cost for many of the producers that we work with is increasing as they have to invest quite a lot of money (and suffer poorer yields) whilst they attack this problem; which makes it incredibly tough for them. However, it was very good to see that all of the farms we work with were very actively responding to the problem. 

The other thing that we are very conscious of is that we must take extra care in cupping and selecting our coffees as we need to ensure that the coffees have been carefully sorted and the impact of Roya is not found in the coffees that we purchase. Thankfully this season we have been very pleased with how all of the coffees have landed which is good!

Tagged : News, Sustainability, Origins, Specialty

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