Shade-grown coffee is, as the name would suggest, a method of farming in which coffee plants are grown underneath a canopy of trees.
The Colombian Coffee Hub has referred to it as an "alternative method of sustainable production" – something which is a central tenet to many in the coffee-trading industry.
In a nutshell, the process of shade-growing facilitates a microclimate which favours the production of coffee in areas where the climate might render it otherwise impossible. Providing shaded environments using carefully selected tree species in this way realises a stable environment beneath the canopy, which favours the growth and flowering of the crops, with gentler ripening of the cherries and protection from the scorching rays of the sun.
It also helps to regulate how the rainfall affects the crop and avoids problems from run-off, which can cause soil erosion and mean the crops don't get enough water. Furthermore, run-off contributes to the leaching of nutrients from the soil, which may prove devastating to coffee production.
In terms of shade-growing as a sustainable practice affecting the people as opposed to the product itself, by helping to drive the coffee industry in otherwise potentially problematic areas, it safeguards the income which so many people rely on for their livelihood.
Understandably, it is therefore employed in certain regions where the sun's rays are far more intense and, depending on the topography, last for more hours during the day. However, it depends purely on the climate of a particular coffee-growing region as to whether or not this kind of farming is preferable.
Another factor concerning the application of shade-grown techniques is if the soil has been particularly eroded or is not at all rich in the organic material and nutrients needed for the crop to grow and thrive, as leaf litter from the trees also helps to contribute essential organic elements like carbon and nitrogen to the soil.
Growers will experiment with a varied and diverse range of tree species to get the balance right, providing the appropriate and optimum shade to help the crops thrive and also contribute to the biodiversity of the soil. In some cases, the right shade will occur naturally, whereas in others it will be a case of growers bringing the right conditions to fruition using their expertise and knowledge.
It is also worth mentioning that shade-grown coffee is not necessarily 'better' than coffee that isn't produced in this way – it is just different and, as with all things, variety is indeed the spice of the coffee industry!
Case study: Santander, Colombia
Extension service engineer Luis Hernan Torres told the Colombian Coffee Hub that 95 per cent of the coffee in Santander in Colombia is shade-grown.
Stating that the ideal rainfall in Santander for shade-grown coffee is around 1,800 to 2,000 mm per year (with the two rainy periods from March to May and September to November), he added: "It is important to regulate the shade so that water does not stay in the tree tops and reaches the whole plant's system."
This illustrates how shade-growing is such a meticulous and delicate skill for farmers to master. Naturally, if there is too much shade, not enough rain will make it to the ground which would render the entire process completely futile.
Santander extension service leader Henry Parra explained how they experiment with different types and varieties of shade species (for example, Inga and Erytrinas trees) depending on what they can bring to the nutrient-deprived soil and contribute to the microclimate underneath the canopy.