Coffee Varieties

Coffee has two main varieties, Arabica and Robusta.

Coffee is one of the most important cash crops in Kenya. It is grown in large scale plantations (42,000 ha from 2001-2005) as well as by small scale holders (128,000 ha from 2001-2005) giving a total production of about 50,000 tons annually. The main variety in Kenya is Arabica coffee.iStock farmer

The stimulating effect of the coffee beverage is largely derived from the alkaloid caffeine, but cured beans have to be roasted and finely ground to bring out the characteristic coffee aroma. In some producer countries, roasting of locally available coffee in the home is very common and the brew is prepared by pouring hot water over freshly roasted and ground coffee beans.

An important constituent of the coffee bean is caffeine. The free caffeine content in a bean is dependant on the coffee type, variety, the site conditions and other factors, and can be more than 2.5%.

Economically, the most important coffee varieties are Coffee arabica called Arabica and Coffee canephora called Robusta. In comparison with Arabica, almost 30 % higher yields are gained from Robusta, although the price is around 30% lower. Coffee is mainly grown as a beverage, though the plant residues can provide fuel (coffee charcoal or wood) and a good mulch.

Until now, organic cultivation has been of less importance in such regions as Ethiopia, Kenya and Mozambique. It is mostly organic .Arabica that is being cultivated.Robusta is currently barely available in certified organic quality.

Coffee Plants come in two main varieties :-

Arabica and RobustaiStock greenbeans

Arabica beans are mild in the cup, with comparatively less caffeine, while Robusta has more aromatic. The Robusta tree appears bushier, the leaves are larger and the berries form in clusters

Coffee Research Foundation (CRF) currently produces four commercial cultivars (varieties) of Arabica coffee. Different varieties are recommended for various altitudes.

i) K7 – low altitude coffee areas with serious Coffee Leaf Rust (CLR).

ii) SL 28 – medium to high coffee areas without serious CLR.

iii) SL 34 – high coffee zone with good rainfall.

iv) Ruiru 11– all coffee growing areas. Resistant to both Coffee Berry Disease(CBD)CLR.

Arabica versus Robusta

The following table presents the main differences between Arabica and Robusta coffee.

Differences between Arabica and Robusta

 

Arabica

Robusta

Time from flower to ripe cherry

9 months

10-11 months

Flowering

After rain

Irregular

Ripe cherry

Fall

Stay

Yield (kg beans/ha)

1500-3000

2300-4000

Root system

Deep

Shallow

Optimum temperature

15-24 C.

24-30 C.

Optimum rainfall

1500-2000 mm

2000-3000 mm

Optimum altitude

1000-2000 m

0-700 m