Chapter 1
Coffee plant & site selection

Coffee is a key industry of Lao PDR being the fifth largest export earner for the country. The French first planted coffee in Lao PDR in the early 1900s on the Bolovens Plateaux in southern Lao. Initially Robusta, Arabica and Liberica species were planted, but due to Arabica leaf rust disease and low prices for Liberica, Robusta has become the dominant coffee species grown. About the same time, new hybrid Arabica coffee was brought to Lao in a bid to stimulate the Arabica coffee industry. This Catimor variety of Arabica is resistant to the major disease of coffee leaf rust.

Coffee is the dominant farming system on the Bolovens Plateaux, which cover an area of about 500 sq. km, ranging across altitudes of 600 to 1300 m.a.s.l. (metres above sea level), at about latitude 15°North. This area produces about 95% of Lao coffee. Arabica coffee has been planted in recent years in a number of the northern provinces of Lao PDR, but to date the relatively small volume of coffee beans produced has not encouraged processing and marketing.

Lao is at now beginning a major change in its coffee industry. In today's world coffee market, in which Lao PDR produces 0.25% of the world production, the emphasis is to move production to higher-value Arabica rather than the lower-value Robusta coffee that is the current mainstay of the industry.

The Government of Lao-PDR plans to increase planting of Arabica to create a balance of 50:50 Arabica:Robusta. Lao 2001 figures indicate that there were 34,000 hectares planted to coffee (88% Robusta and 12% Arabica) and that 23,000 families were involved in coffee production.

The coffee industry in Lao PDR is a mixture of smallholder and large estates. Management systems range from high input intensive systems to smallholders with zero inputs and low yields. Large estates have their own processing and branding, with one company currently producing their own instant coffee.

Lao has the potential to grow large amounts of high quality Arabica coffee. It has a very suitable climate, abundant land resources and farmers who are eager for a viable cash crop. The volcanic red earth soils and climate of the upper elevations of the Bolovens Plateaux are an excellent area to develop a specialised and valuable coffee industry. Although the Government of Lao is interested in developing this industry and there is a clear market for good quality Lao Arabica coffee, it lacks funding support for the essential research, development and extension to support the emerging industry.

There is also an opportunity to produce value-added 'washed/semi-washed' Robusta coffee as Lao Robustas are already sought for their clean, good bodied, neutral characters. Lao is atypical in that a large quantity of Robusta is grown at high altitudes of up to 1300 m.a.s.l. resulting in some unusual characteristics in this coffee. New processing, pulping and demucilaging technologies have been introduced by the FAO project to improve both Arabica and Robusta quality at affordable costs. These will offer some new opportunities for both coffee Arabica and Robusta coffees.

Factors affecting yield and quality

There are three factors which impact greatly on coffee yield and quality.

• Genetics (Genotype-species and varieties to plant)

• Environment

• The coffee plant and its management

Genotype species and varieties to plant

Species

There are two main species of commercial coffee - Coffea arabica and C. canephora (robusta) and two minor commercial species - Coffea liberica and Coffea excelsa.

Arabica is a higher quality and higher value coffee normally grown in cooler, elevated areas of the tropics and sub-tropics at 1000 m or more above sea level. Arabica is used in the roast and ground coffee market and is added to blends of Robusta to improve the quality of instant coffee. Brazil and Columbia are the major producing countries.

Robusta is a lower quality coffee and prices are normally about 30 to 40% less than Arabica. Robusta is used mainly in instant coffee and for blending with Arabicas to add body and crema. Robusta is normally grown in warmer areas at lower elevations unsuited to Arabica, and is considered resistant/tolerant to coffee rust. Lao PDR is an exception to this in that Robusta is grown at higher elevations (up to nearly 1300 m.a.s.l.). Vietnam, Brazil and Indonesia are the largest Robusta producing countries. Compared with Arabica, Robusta is generally more vigorous, more productive and less vulnerable to rust.

Liberica and Excelsa are grown mainly in low, hot climate areas. Quality is poor and markets are limited. These coffees are of local importance in a few countries and not of major commercial significance in the international coffee market. Both are present in the older Lao plantations, but have little future in the era of high quality coffee.

For Arabica, the improvement of genotype is achieved by proper choice of variety (cultivar). The variety of choice should ideally have the following characteristics:

• dwarfish or compact growth;

• high yield;

• leaf rust resistance, and

• outstanding cup quality.

Varieties to plant

Coffee is a long-term crop with a lifespan of more than 10 years, and considerably longer under good management, thus the choice of variety (cultivar) is very important. As quality of the coffee bean is crucial for production of high-grade coffee, choose only varieties that are recommended for your area. These will be the best yielding, best quality varieties that will grow productively in the local soils and climate.

For the Bolovens Plateaux the recommended Arabica cultivars are:

Arabica (especially at elevations above 1000 m.a.s.l.):

Java
Typica

Other varieties are being tested at the Coffee Research Experimentation Centre and Dao Heuang Farm near Paksong (1180 m.a.s.l.). CREC will advise in the future those varieties that are suitable for planting after trials and cupping tests are completed. Comments on these varieties and others of significance being tested at CREC and Dao Heuang include these listed below and on the following pages.

Typica

Java

S 795

Caturra

Catuai

SL 34

SL 28

SL 6

Catimor

Environment (site selection)

To grow and produce good quality coffee, several important environmental factors should be taken into account. These include:

• Elevation and temperature;

• Rainfall and water supply;

• Soil;

• Aspect and slope.

Elevation

Elevation influences a number of these factors and must be considered along with temperature, rainfall and water supply, soil, slope and aspect when determining where to plant coffee. An elevation greater than 1000 m above sea level (m.a.s.l.) is required for Arabica coffee. Low elevation Arabica coffee does not possess the quality required by the world markets. In Lao PDR, areas above 1000 metres are preferred for production of superior quality coffee and the Bolovens Plateaux have ample areas of land at 1000 to 1300 m.a.s.l.

High elevation improves the quality of the bean and potential cupping quality. Due to a delay in ripening brought about by cooler weather associated with higher altitudes, the inherent characteristics of acidity, aroma and bold bean can develop fully. (Bold bean is classified as being the size between a large and a medium sized bean, with its width/ length ratio bigger than that of a large bean).

Temperature

Arabica coffee prefers a cool temperature with an optimum daily temperature of between 20° to 24°C. The average mean temperatures of selected areas of the Bolovens Plateaux (Figure 1) are:

Temperatures greater than 30°C cause plant stress leading to a cessation of photosynthesis. Mean temperatures of less than 15°C limit plant growth and are considered sub-optimal. Arabica coffee is frost susceptible. Use of shade trees will reduce the incidence of frost.

Rainfall and water supply

Ideal rainfall for Arabica coffee is greater than 1200 to 1500 mm per year. Both the total amount and the distribution pattern are important. Annual rainfall on the Bolovens Plateaux (Figure 2) is:

Rain should to be uniformly distributed over seven to nine months of the year, as is the case especially at higher elevations on the Bolovens Plateaux. At lower elevations, the dry season is often too pronounced. Lack of rainfall in either amount or timing can be compensated for by using irrigation.

Figure 1. Mean monthly temperatures on the Bolovens Plateaux

Figure 2. Mean monthly rainfall on the Bolovens Plateaux

Coffee needs a dry, stress period with little or no rain to induce a uniform flowering. Without a stress period, flowering many extend over many months making harvesting more difficult. Lao normally has such a stress period of three to four months of dry weather at elevations of 1000 m.a.s.l. or more.

Soil type

For successful production, a free draining soil with a minimum depth of one metre is required. Coffee will not tolerate waterlogging or 'wet feet'.

Coffee can be grown on many different soil types, but the ideal is a fertile, volcanic red earth or a deep, sandy loam. Yellow-brown, high silt soils are less preferred. Avoid heavy clay or poor-draining soils. Most soils on the Bolovens Plateaux are volcanic red earths suitable for coffee.

Coffee prefers a soil with pH of 5 to 6. Many cultivated soils of the Bolovens Plateaux are acid (less than pH 5) and need lime or dolomite. Few soil test results exist, but indicator plants point to a pH less than 5 with low available phosphorus and thus shortages of many other nutrients. Low pH will limit crop performance by upsetting the availability of key nutrients to coffee plants (see Figure 3).

Good management and applications of dolomite or lime can alter and improve soil pH and fertility.

Figure 3. Effect of soil pH on nutrient availability

Slope and aspect (slope % and direction)

An easterly or southern facing aspect with a slope less than 15% is preferable. Most locations on the Bolovens Plateaux have a gentle slope and no extra measures are required. Steeper slopes present a major erosion risk and require terracing or special management such as contour furrows or preferably grass strips.

A slight slope will improve air drainage and reduce damage from frost. Do not plant coffee at the bottom of a slope or in shallow dips where cold air can pool, as frost damage is more likely here. Usually it is best not to plant the bottom third of a slope as it will be colder and sometimes waterlogged.

Exposed aspects subject to strong winds, should either be avoided or windbreaks such as Silver Oak (Grevillea robusta) established before planting the coffee trees.

Water supply

Coffee requires adequate water during the growing and cropping period, however it also requires a dry stress period followed by sufficient rain or irrigation to promote uniform flowering and a good fruit set.

Many plantings suffer from moisture stress at the time of year when they need adequate water for growth and cropping (see the phenological cycle page 70). The local rainfall pattern indicates that supplemental irrigation, especially to induce uniform flowering and good fruit set, would be beneficial. Unless regular rain is received, young trees should be irrigated (or hand watered at least twice a week if irrigation is not available) to ensure establishment of the newly planted trees. Locating coffee plantings near a water supply for possible irrigation as well as for processing of cherry is desirable.

Water requirements can be reduced by use of proper, well-established, shade trees, mulch and cover crops. These practices are discussed in later sections.

The coffee plant and its management

An understanding of the coffee plant, its make up and how it grows is essential to understanding how to manage the coffee tree. Management, like the growing environment and the variety planted, has a very big influence on coffee quality and yield. Much of the rest of this manual deals with practical management of the coffee tree from planting to harvest.

Figure 4. Diagram showing parts of the coffee plant (above) and tree habit (below)

The shape of the coffee plant varies depending on the species and variety. All coffee trees consist of an upright main shoot (trunk) with primary, secondary and tertiary lateral branches. The plant has a main taproot, lateral and small feeder roots (see Figure 4). The coffee tree produces two distinct types of branches:

• Vertical or orthotropic branches have nodes at a regular distance and carry opposite leaves. These branches are called suckers at the developing stage and stems at the final stage. Each leaf pair is cross-positioned to the next leaf pair. In the axil of each leaf, are four to six serial buds and directly above them, one slightly bigger bud called 'extra-axillary bud' because of its relatively distant position. This extra-axillary bud develops into a plagiotropic or lateral, horizontal branch.

• Lateral or plagiotropic branches grow almost at right angles from the main stems. No other bud in the same axil can grow into a lateral branch, which means that if such a branch is cut off, no lateral regeneration can occur on the node of a main vertical stem. Laterals are usually called primaries. Each serial bud on a primary can develop into an inflorescence (flower) or into a secondary branch, which has a similar structure to the primary branch with serial buds that develop either into flowers or tertiary branches. If a secondary branch is cut or removed, another secondary on the same axil can replace it, so regeneration of secondaries on primaries is possible.

Each branch has a terminal bud. In the nodes are a fixed number of buds that have the potential to form 40 fruits depending mainly on the species and nutritional conditions. At each leaf node there are 5 buds each with 4 flowers, which may form 20 fruits (Figure 5).

The white flowers appear in small bunches at the nodes. After pollination, a fruit develops into a cherry about 10 to 15 mm long containing two seeds (the coffee beans). Technically, the flowers form on the one-year-old wood that is only slightly hardened. The fruits comprise pulp (coloured skin and a fleshy mesocarp called mucilage), then parchment, then the silverskin (seed coat) and finally the coffee bean (Figure 6).

Figure 5. Potential of yields (left and diagram above

Figure 6. Coffee cherries from green to ripe (above) and diagram showing parts of the cherry (right)

The root system

The role of the root system is to ensure that the plant is firmly anchored in the soil and to take up a supply of water and minerals. The root system (Figure 7) consists of:

• a short taproot (40 to 60 cm) long;

• vertical, coaxial roots which are often very long (particularly in light soils) lateral roots with numerous absorbing root hairs, particularly in the upper, humus-bearing layer (30 cm)

Figure 7. Root system

It is necessary to stress the importance of growing techniques (pricking out in nurseries, weeding, mulching, irrigation and planting layouts) on the distribution and function of the roots. The first three years are critical for the root system development when it is vital that plants are well supplied with nitrogen, phosphorous, calcium, magnesium and sulphur.

Phenology (Crop cycle)

The phenology of the coffee plant refers to the physical and physiological developmental stages of the coffee plant throughout the year. Phenology is often referred to as the crop cycle or the phenological cycle of the plant.

Coffee, like all plants responds to the changing environment (temperature, rainfall, drought, day length) in which it grows as influenced by the seasons. As the seasons change, the coffee tree switches from vegetative (root and shoot growth) to reproductive growth and as the plant grows, it flowers, sets fruit, matures the fruit and is ready for harvest and re-growth for the next cycle.

The phenological cycle gives excellent indicators of when to fertilise, irrigate, withhold water, prune, take leaf and soil analyses, check for pests and diseases and apply controls for them. Timing is very important when using these practices to optimise production from the coffee tree.